A road is a thoroughfare, route, or way on land between two places that has been paved or otherwise improved to allow travel by foot or some form of conveyance, including a motor vehicle, cart, bicycle, or horse.
Roads consist of one or two roadways (British English: carriageways), each with one or more lanes and any associated sidewalks (British English: pavement) and road verges. There is sometimes a bike path. Other names for roads include parkways, avenues, freeways, tollways, interstates, highways, or primary, secondary, and tertiary local roads.
Historically many roads were simply recognizable routes without any formal construction or maintenance.
The Organisation for Economic Co-operation and Development (OECD) defines a road as "a line of communication (travelled way) using a stabilized base other than rails or air strips open to public traffic, primarily for the use of road motor vehicles running on their own wheels", which includes "bridges, tunnels, supporting structures, junctions, crossings, interchanges, and toll roads, but not cycle paths".
The Eurostat, ITF and UNECE Glossary for Transport Statistics Illustrated defines a road as a "Line of communication (travelled way) open to public traffic, primarily for the use of road motor vehicles, using a stabilized base other than rails or air strips. [...] Included are paved roads and other roads with a stabilized base, e.g. gravel roads. Roads also cover streets, bridges, tunnels, supporting structures, junctions, crossings and interchanges. Toll roads are also included. Excluded are dedicated cycle lanes."
In urban areas roads may diverge through a city or village and be named as streets, serving a dual function as urban space easement and route. Modern roads are normally smoothed, paved, or otherwise prepared to allow easy travel.
In the United Kingdom The Highway Code details rules for "road users", but there is some ambiguity between the terms highway and road. For the purposes of the English law, Highways Act 1980, which covers England and Wales but not Scotland or Northern Ireland, road is "any length of highway or of any other road to which the public has access, and includes bridges over which a road passes". This includes footpaths, bridleways and cycle tracks, and also road and driveways on private land and many car parks. Vehicle Excise Duty, a road use tax, is payable on some vehicles used on the public road.
The definition of a road depends on the definition of a highway; there is no formal definition for a highway in the relevant Act. A 1984 ruling said "the land over which a public right of way exists is known as a highway; and although most highways have been made up into roads, and most easements of way exist over footpaths, the presence or absence of a made road has nothing to do with the distinction. Another legal view is that while a highway historically included footpaths, bridleways, driftways, etc., it can now be used to mean those ways that allow the movement of motor-vehicles, and the term rights of way can be used to cover the wider usage.
In the United States, laws distinguish between public roads, which are open to public use, and private roads, which are privately controlled.
Maintenance is becoming an increasing problem in the United States. Between 1997 and 2018, the number of existing roads too bumpy to drive on compared to roads with decent surfaces has increased by 11%, mostly due to potholes that are not being properly addressed.
The assertion that the first pathways were the trails made by animals has not been universally accepted; in many cases animals do not follow constant paths. Some believe that some roads originated from following animal trails. The Icknield Way may examplify this type of road origination, where human and animal both selected the same natural line. By about 10,000 BC human travelers used rough roads/pathways.
Road design is part of highway engineering. Structural road design is designing a road for its environment in order to extend its longevity and reduce maintenance. The Shell pavement design method is used in many countries for the design of new asphalt roadsides.
vehicles other than motor cycles.
In transport engineering, subgrade is the native material underneath a constructed road
Road construction requires the creation of an engineered continuous right-of-way or roadbed, overcoming geographic obstacles and having grades low enough to permit vehicle or foot travel,:15 and may be required to meet standards set by law or official guidelines. The process is often begun with the removal of earth and rock by digging or blasting, construction of embankments, bridges and tunnels, and removal of vegetation (this may involve deforestation) and followed by the laying of pavement material. A variety of road building equipment is employed in road building.
After design, approval, planning, legal and environmental considerations have been addressed alignment of the road is set out by a surveyor. The radii and gradient are designed and staked out to best suit the natural ground levels and minimize the amount of cut and fill.:34 Great care is taken to preserve reference Benchmarks :59
Roads are designed and built for primary use by vehicular and pedestrian traffic. Storm drainage and environmental considerations are a major concern. Erosion and sediment controls are constructed to prevent detrimental effects. Drainage lines are laid with sealed joints in the road easement with runoff coefficients and characteristics adequate for the land zoning and storm water system. Drainage systems must be capable of carrying the ultimate design flow from the upstream catchment with approval for the outfall from the appropriate authority to a watercourse, creek, river or the sea for drainage discharge.:38–40
A borrow pit (source for obtaining fill, gravel, and rock) and a water source should be located near or in reasonable distance to the road construction site. Approval from local authorities may be required to draw water or for working (crushing and screening) of materials for construction needs. The topsoil and vegetation is removed from the borrow pit and stockpiled for subsequent rehabilitation of the extraction area. Side slopes in the excavation area not steeper than one vertical to two horizontal for safety reasons.:53–56
Old road surfaces, fences, and buildings may need to be removed before construction can begin. Trees in the road construction area may be marked for retention. These protected trees should not have the topsoil within the area of the tree's drip line removed and the area should be kept clear of construction material and equipment. Compensation or replacement may be required if a protected tree is damaged. Much of the vegetation may be mulched and put aside for use during reinstatement. The topsoil is usually stripped and stockpiled nearby for rehabilitation of newly constructed embankments along the road. Stumps and roots are removed and holes filled as required before the earthwork begins. Final rehabilitation after road construction is completed will include seeding, planting, watering and other activities to reinstate the area to be consistent with the untouched surrounding areas.:66–67
Processes during earthwork include excavation, removal of material to spoil, filling, compacting, construction and trimming. If rock or other unsuitable material is discovered it is removed, moisture content is managed and replaced with standard fill compacted to meet the design requirements (generally 90–95% relative compaction). Blasting is not frequently used to excavate the roadbed as the intact rock structure forms an ideal road base. When a depression must be filled to come up to the road grade the native bed is compacted after the topsoil has been removed. The fill is made by the "compacted layer method" where a layer of fill is spread then compacted to specifications, under saturated conditions. The process is repeated until the desired grade is reached.:68–69
General fill material should be free of organics, meet minimum California bearing ratio (CBR) results and have a low plasticity index. The lower fill generally comprises sand or a sand-rich mixture with fine gravel, which acts as an inhibitor to the growth of plants or other vegetable matter. The compacted fill also serves as lower-stratum drainage. Select second fill (sieved) should be composed of gravel, decomposed rock or broken rock below a specified particle size and be free of large lumps of clay. Sand clay fill may also be used. The roadbed must be "proof rolled" after each layer of fill is compacted. If a roller passes over an area without creating visible deformation or spring the section is deemed to comply.:70–72
Geosynthetics such as geotextiles, geogrids and geocells are frequently used in the various pavement layers to improve road quality. These materials and methods are used in low-traffic private roadways as well as public roads and highways. Geosynthetics perform four main functions in roads: separation, reinforcement, filtration and drainage; which increase the pavement performance, reduce construction costs and decrease maintenance.
The completed road way is finished by paving or left with a gravel or other natural surface. The type of road surface is dependent on economic factors and expected usage. Safety improvements such as traffic signs, crash barriers, raised pavement markers and other forms of road surface marking are installed.
According to a May 2009 report by the American Association of State Highway and Transportation Officials (AASHTO) and TRIP – a national transportation research organization – driving on rough roads costs the average American motorist approximately $400 a year in extra vehicle operating costs. Drivers living in urban areas with populations more than 250,000 are paying upwards of $750 more annually because of accelerated vehicle deterioration, increased maintenance, additional fuel consumption, and tire wear caused by poor road conditions.
When a single carriageway road is converted into dual carriageway by building a second separate carriageway alongside the first, it is usually referred to as duplication, twinning or doubling. The original carriageway is changed from two-way to become one-way, while the new carriageway is one-way in the opposite direction. In the same way as converting railway lines from single track to double track, the new carriageway is not always constructed directly alongside the existing carriageway.
Like all structures, roads deteriorate over time. Deterioration is primarily due to accumulated damage from vehicles, however environmental effects such as frost heaves, thermal cracking and oxidation often contribute. According to a series of experiments carried out in the late 1950s, called the AASHO Road Test, it was empirically determined that the effective damage done to the road is roughly proportional to the Fourth power of axle weight. A typical tractor-trailer weighing 80,000 pounds (36.287 t) with 8,000 pounds (3.629 t) on the steer axle and 36,000 pounds (16.329 t) on both of the tandem axle groups is expected to do 7,800 times more damage than a passenger vehicle with 2,000 pounds (0.907 t) on each axle. Potholes on roads are caused by rain damage and vehicle braking or related construction works.
Pavements are designed for an expected service life or design life. In some parts of the United Kingdom the standard design life is 40 years for new bitumen and concrete pavement. Maintenance is considered in the whole life cost of the road with service at 10, 20 and 30 year milestones. Roads can be and are designed for a variety of lives (8-, 15-, 30-, and 60-year designs). When pavement lasts longer than its intended life, it may have been overbuilt, and the original costs may have been too high. When a pavement fails before its intended design life, the owner may have excessive repair and rehabilitation costs. Some asphalt pavements are designed as perpetual pavements with an expected structural life in excess of 50 years.
Many asphalt pavements built over 35 years ago, despite not being specifically designed as a perpetual pavement, have remained in good condition long past their design life. Many concrete pavements built since the 1950s have significantly outlived their intended design lives. Some roads like Chicago, Illinois's "Wacker Drive", a major two-level viaduct in the downtown area, are being rebuilt with a designed service life of 100 years.
Virtually all roads require some form of maintenance before they come to the end of their service life. Pro-active agencies use pavement management techniques to continually monitor road conditions and schedule preventive maintenance treatments as needed to prolong the lifespan of their roads. Technically advanced agencies monitor the road network surface condition with sophisticated equipment such as laser/inertial Profilometers. These measurements include road curvature, cross slope, asperity, roughness, rutting and texture. Software algorithms use this data to recommend maintenance or new construction.
Maintenance treatments for asphalt concrete generally include thin asphalt overlays, crack sealing, surface rejuvenating, fog sealingfo, micro milling or diamond grinding and surface treatments. Thin surfacing preserves, protects and improves the functional condition of the road while reducing the need for routing maintenance, leading to extended service life without increasing structural capacity.
Older concrete pavements that develop faults can be repaired with a dowel bar retrofit, in which slots are cut in the pavement at each joint, and dowel bars are placed in the slots, which are then filled with concrete patching material. This can extend the life of the concrete pavement for 15 years.
Failure to maintain roads properly can create significant costs to society, in a 2009 report released by the American Association of State Highway and Transportation Officials (US) about 50% of the roads in the US are in bad condition with urban areas worse. The report estimates that urban drivers pay an average of $746/year on vehicle repairs while the average US motorist pays about $335/year. In contrast, the average motorist pays about $171/year in road maintenance taxes (based on 600 gallons/year and $0.285/gallon tax).
Distress and serviceability loss on concrete roads can be caused by loss of support due to voids beneath the concrete pavement slabs. The voids usually occur near cracks or joints due to surface water infiltration. The most common causes of voids are pumping, consolidation, subgrade failure and bridge approach failure. Slab stabilization is a non-destructive method of solving this problem and is usually employed with other Concrete Pavement Restoration (CPR) methods including patching and diamond grinding. The technique restores support to concrete slabs by filing small voids that develop underneath the concrete slab at joints, cracks or the pavement edge.
The process consists of pumping a cementitous grout or polyurethane mixture through holes drilled through the slab. The grout can fill small voids beneath the slab and/or sub-base. The grout also displaces free water and helps keep water from saturating and weakening support under the joints and slab edge after stabilization is complete. The three steps for this method after finding the voids are locating and drilling holes, grout injection and post-testing the stabilized slabs.
Slab stabilization does not correct depressions, increase the design structural capacity, stop erosion or eliminate faulting. It does, however, restore the slab support, therefore, decreasing deflections under the load. Stabilization should only be performed at joints and cracks where loss of support exists. Visual inspection is the simplest manner to find voids. Signs that repair is needed are transverse joint faulting, corner breaks and shoulder drop off and lines at or near joints and cracks. Deflection testing is another common procedure utilized to locate voids. It is recommended to do this testing at night as during cooler temperatures, joints open, aggregate interlock diminishes and load deflections are at their highest.
Ground penetrating radar pulses electromagnetic waves into the pavement and measures and graphically displays the reflected signal. This can reveal voids and other defects.
The epoxy/core test, detects voids by visual and mechanical methods. It consists of drilling a 25 to 50 millimeter hole through the pavement into the sub-base with a dry-bit roto-hammer. Next, a two-part epoxy is poured into the hole – dyed for visual clarity. Once the epoxy hardens, technicians drill through the hole. If a void is present, the epoxy will stick to the core and provide physical evidence.
Common stabilization materials include pozzolan-cement grout and polyurethane. The requirements for slab stabilization are strength and the ability to flow into or expand to fill small voids. Colloidal mixing equipment is necessary to use the pozzolan-cement grouts. The contractor must place the grout using a positive-displacement injection pump or a non-pulsing progressive cavity pump. A drill is also necessary but it must produce a clean hole with no surface spalling or breakouts. The injection devices must include a grout packer capable of sealing the hole. The injection device must also have a return hose or a fast-control reverse switch, in case workers detect slab movement on the uplift gauge. The uplift beam helps to monitor the slab deflection and has to have sensitive dial gauges.
Also called joint and crack repair, this method's purpose is to minimize infiltration of surface water and incompressible material into the joint system. Joint sealants are also used to reduce dowel bar corrosion in Concrete Pavement Restoration (CPR) techniques. Successful resealing consists of old sealant removal, shaping and cleaning the reservoir, installing the backer rod and installing the sealant. Sawing, manual removal, plowing and cutting are methods used to remove the old sealant. Saws are used to shape the reservoir. When cleaning the reservoir, no dust, dirt or traces of old sealant should remain. Thus, it is recommended to water wash, sand-blast and then air blow to remove any sand, dirt or dust. The backer rod installation requires a double-wheeled, steel roller to insert the rod to the desired depth. After inserting the backer rod, the sealant is placed into the joint. There are various materials to choose for this method including hot pour bituminous liquid, silicone and preformed compression seals.
Careful design and construction of roads can increase road traffic safety and reduce the harm (deaths, injuries, and property damage) on the highway system from traffic collisions.
Lane markers in some countries and states are marked with Cat's eyes or |Botts dots, bright reflectors that do not fade like paint. Botts dots are not used where it is icy in the winter, because frost and snowplows can break the glue that holds them to the road, although they can be embedded in short, shallow trenches carved in the roadway, as is done in the mountainous regions of California.
For major roads risk can be reduced by providing limited access from properties and local roads, grade separated junctions and median dividers between opposite-direction traffic to reduce likelihood of head-on collisions.
The placement of energy attenuation devices (e.g. guardrails, wide grassy areas, sand barrels) is also common. Some road fixtures such as road signs and fire hydrants are designed to collapse on impact. Light poles are designed to break at the base rather than violently stop a car that hits them. Highway authorities may also remove larger trees from the immediate vicinity of the road. During heavy rains, if the elevation of the road surface isn't higher than the surrounding landscape, it may result in flooding.
Speed limits can improve road traffic safety and reduce the number of road traffic casualties from traffic collisions. In their World report on road traffic injury prevention report, the World Health Organization (WHO) identify speed control as one of various interventions likely to contribute to a reduction in road casualties.
Road conditions are the collection of factors describing the ease of driving on a particular stretch of road, or on the roads of a particular locality, including the quality of the pavement surface, potholes, road markings, and weather. It has been reported that "[p]roblems of transportation participants and road conditions are the main factors that lead to road traffic accidents". It has further been specifically noted that "weather conditions and road conditions are interlinked as weather conditions affect the road conditions". Specific aspects of road conditions can be of particular importance for particular purposes. For example, for autonomous vehicles such as self-driving cars, significant road conditions can include "shadowing and lighting changes, road surface texture changes, and road markings consisting of circular reflectors, dashed lines, and solid lines".
Various government agencies and private entities, including local news services, track and report on road conditions to the public, so that drivers going through a particular area can be aware of hazards that may exist in that area. News agencies, in turn, rely on tips from area residents with respect to certain aspects of road conditions in their coverage area.
Careful design and construction of a road can reduce any negative environmental impacts.
Water management systems can be used to reduce the effect of pollutants from roads. Rainwater and snowmelt running off of roads tends to pick up gasoline, motor oil, heavy metals, trash and other pollutants and result in water pollution. Road runoff is a major source of nickel, copper, zinc, cadmium, lead and polycyclic aromatic hydrocarbons (PAHs), which are created as combustion byproducts of gasoline and other fossil fuels.
De-icing chemicals and sand can run off into roadsides, contaminate groundwater and pollute surface waters; and road salts can be toxic to sensitive plants and animals. Sand applied to icy roads can be ground up by traffic into fine particulates and contribute to air pollution.
Roads are a chief source of noise pollution. In the early 1970s it was recognized that design of roads can be conducted to influence and minimize noise generation. Noise barriers can reduce noise pollution near built-up areas. Regulations can restrict the use of engine braking.
Motor vehicle emissions contribute air pollution. Concentrations of air pollutants and adverse respiratory health effects are greater near the road than at some distance away from the road. Road dust kicked up by vehicles may trigger allergic reactions. In addition, on-road transportation greenhouse gas emissions are the largest single cause of climate change, scientists say.
Traffic flows on the right or on the left side of the road depending on the country. In countries where traffic flows on the right, traffic signs are mostly on the right side of the road, roundabouts and traffic circles go counter-clockwise/anti-clockwise, and pedestrians crossing a two-way road should watch out for traffic from the left first. In countries where traffic flows on the left, the reverse is true.
About 33% of the world by population drive on the left, and 67% keep right. By road distances, about 28% drive on the left, and 72% on the right, even though originally most traffic drove on the left worldwide.
Transport economics is used to understand both the relationship between the transport system and the wider economy and the complex network effects when there are multiple paths and competing modes for both personal and freight (road/rail/air/ferry) and where Induced demand can result in increased on decreased transport levels when road provision is increased by building new roads or decreased (for example California State Route 480). Roads are generally built and maintained by the public sector using taxation although implementation may be through private contractors). or occasionally using road tolls.
Society depends heavily on efficient roads. In the European Union (EU) 44% of all goods are moved by trucks over roads and 85% of all people are transported by cars, buses or coaches on roads. The term was also commonly used to refer to roadsteads, waterways that lent themselves to use by shipping.
According to the New York State Thruway Authority, some sample per-mile costs to construct multi-lane roads in several US northeastern states were:
The United States has the largest network of roads of any country with 4,050,717 miles (6,518,997 km) as of 2009. The Republic of India has the second largest road system in the world with 4,689,842 kilometres (2,914,133 mi) of road (2013). The People's Republic of China is third with 3,583,715 kilometres (2,226,817 mi) of road (2007). The Federative Republic of Brazil has the fourth largest road system in the world with 1,751,868 kilometres (1,088,560 mi) (2002). See List of countries by road network size. When looking only at expressways the National Trunk Highway System (NTHS) in China has a total length of 45,000 kilometres (28,000 mi) at the end of 2006, and 60,300 km at the end of 2008, second only to the United States with 90,000 kilometres (56,000 mi) in 2005. However, as of 2017 China has 130,000 km of Expressways.
Eurasia, Africa, North America, South America, and Australia each have an extensive road network that connects most cities. The North and South American road networks are separated by the Darién Gap, the only interruption in the Pan-American Highway. Eurasia and Africa are connected by roads on the Sinai Peninsula. The European Peninsula is connected to the Scandinavian Peninsula by the Øresund Bridge, and both have many connections to the mainland of Eurasia, including the bridges over the Bosphorus. Antarctica has very few roads and no continent-bridging network, though there are a few ice roads between bases, such as the South Pole Traverse. Bahrain is the only island country to be connected to a continental network by road (the King Fahd Causeway to Saudi Arabia). Even well-connected road networks are controlled by many different legal jurisdictions, and laws such as which side of the road to drive on vary accordingly.
Many populated domestic islands are connected to the mainland by bridges. A very long example is the 113 mi (182 km) Overseas Highway connecting many of the Florida Keys with the continental United States.
Even on mainlands, some settlements have no roads connecting with the primary continental network, due to natural obstacles like mountains or wetlands, remoteness, or general expense. Unpaved roads or lack of roads are more common in developing countries, and these can become impassible in wet conditions. As of 2014, only 43% of rural Africans have access to an all-season road. Due to steepness, mud, snow, or fords, roads can sometimes be passable only to four-wheel drive vehicles, those with snow chains or snow tires, or those capable of deep wading or amphibious operation.
Cities on the mainland of continents which do not have road access include:
Most disconnected settlements have local road networks connecting ports, buildings, and other points of interest.
Where demand for travel by road vehicle to a disconnected island or mainland settlement is high, roll-on/roll-off ferries are commonly available if the journey is relatively short. For long-distance trips, passengers usually travel by air and rent a car upon arrival. If facilities are available, vehicles and cargo can also be shipped to many disconnected settlements by boat, or air transport at much greater expense. The island of Great Britain is connected to the European road network by Eurotunnel Shuttle – an example of a car shuttle train which is a service used in other parts of Europe to travel under mountains and over wetlands.
In polar areas, disconnected settlements are often more easily reached by snowmobile or dogsled in cold weather, which can produce sea ice that blocks ports, and bad weather that prevents flying. For example, resupply aircraft are only flown to Amundsen–Scott South Pole Station October to February, and many residents of coastal Alaska have bulk cargo shipped in only during the warmer months. Permanent darkness during the winter can also make long-distance travel more dangerous in polar areas. Continental road networks do reach into these areas, such as the Dalton Highway to the North Slope of Alaska, the R21 highway to Murmansk in Russia, and many roads in Scandinavia (though due to fjords water transport is sometimes faster). Large areas of Alaska, Canada, Greenland, and Siberia are sparsely connected. For example, all 25 communities of Nunavut are disconnected from each other and the main North American road network.
Road transport of people and cargo by may also be obstructed by border controls and travel restrictions. For example, travel from other parts of Asia to South Korea would require passage through the hostile country of North Korea. Moving between most countries in Africa and Eurasia would require passing through Egypt and Israel, which is a politically sensitive area.
Some places are intentionally car-free, and roads (if present) might be used by bicycles or pedestrians.
Roads are under construction to many remote places, such as the villages of the Annapurna Circuit, and a road was completed in 2013 to Mêdog County. Additional intercontinental and transoceanic fixed links have been proposed, including a Bering Strait crossing that would connect Eurasia-Africa and North America, a Malacca Strait Bridge to the largest island of Indonesia from Asia, and a Strait of Gibraltar crossing to connect Europe and Africa directly.
"road" – (a) in England and Wales, means any length of highway or of any other road to which the public has access, and includes bridges over which a road passes, and (b) in Scotland, has the same meaning as in the Roads (Scotland) Act 1984
Most of the provisions apply on all roads throughout Great Britain, although there are some exceptions.
The land over which a public right of way exists is known as a highway; and although most highways have been made up into roads, and most easements of way exist over footpaths, the presence or absence of a made road has nothing to do with the distinction. There may be a highway over a footpath, while a well-made road may be subject only to an easement of way, or may exist only for the landowner's benefit and be subject to no easement at all
Historically, a highway comprehended any path in which members of the public had the right to pass and re-pass without let or hindrance. The term embraced footpaths, bridleways, driftways and so forth. The advent of the motor vehicle and its peculiar requirements has seen increasing distinctions between paths over which walkers and riders have a right of way and those ways that are predominantly used by motor vehicles. The former may be usefully termed "rights of way" (and are the subject of a separate entry in this web) and the latter may be termed "highways."
ROAD. A passage through the country for the use of the people. 3 Yeates, 421. 2. Roads are public or private. Public roads are laid out by public authority, or dedicated by individuals to public use. The public have the use of such roads, but the owner of the land over which they are made and the owners of land bounded on the highway, have, prima facie, a fee in such highway, ad medium filum viae, subject to the easement in favor of the public... Private roads are, such as are used for private individuals only, and are not wanted for the public generally.
The first sidewalks appeared around 2000 to 1990 B.C. [...] in central Anatolia (modern Turkey) [...].
Abbey Road is the eleventh studio album by English rock band the Beatles, released on 26 September 1969 by Apple Records. The recording sessions for the album were the last in which all four Beatles participated. Although Let It Be was the final album that the Beatles completed before the band's dissolution in April 1970, most of the album had been recorded before the Abbey Road sessions began. A two-sided hit single from the album, "Something" backed with "Come Together", released in October, topped the Billboard Hot 100 chart in the US.
Abbey Road is a rock album that incorporates genres such as blues, pop, and progressive rock, and it makes prominent use of the Moog synthesizer and the Leslie speaker. Side two contains a medley of song fragments edited together to form a single piece. The album was recorded amid a more enjoyable atmosphere than the Get Back/Let It Be sessions earlier in the year, but there were still frequent disagreements within the band. John Lennon had privately left the group by the time the album was released and McCartney publicly quit the following year.
Although Abbey Road was an immediate commercial success and reached No. 1 in the UK and US, it initially received mixed reviews, with some critics describing its music as inauthentic and bemoaning the production's artificial effects. Over time, the album became viewed as among the Beatles' best and many critics have ranked it as one of the greatest albums of all time. In particular, George Harrison's contributions, "Something" and "Here Comes the Sun", are considered to be among the best songs he wrote for the group. The album's cover, which features the four band members walking across a zebra crossing outside Abbey Road Studios, has become one of the most famous and imitated images in the history of popular music.Asphalt
Asphalt, also known as bitumen (UK: , US: ), is a sticky, black, and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used. The word is derived from the Ancient Greek ἄσφαλτος ásphaltos.
The primary use (70%) of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs.The terms "asphalt" and "bitumen" are often used interchangeably to mean both natural and manufactured forms of the substance. In American English, "asphalt" (or "asphalt cement") is commonly used for a refined residue from the distillation process of selected crude oils. Outside the United States, the product is often called "bitumen", and geologists worldwide often prefer the term for the naturally occurring variety. Common colloquial usage often refers to various forms of asphalt as "tar", as in the name of the La Brea Tar Pits.
Naturally occurring asphalt is sometimes specified by the term "crude bitumen". Its viscosity is similar to that of cold molasses while the material obtained from the fractional distillation of crude oil boiling at 525 °C (977 °F) is sometimes referred to as "refined bitumen". The Canadian province of Alberta has most of the world's reserves of natural asphalt in the Athabasca oil sands, which cover 142,000 square kilometres (55,000 sq mi), an area larger than England.Audi R8
The Audi R8 is a mid-engine, 2-seater sports car, which uses Audi's trademark quattro permanent all-wheel drive system. It was introduced by the German car manufacturer Audi AG in 2006.
The car is exclusively designed, developed, and manufactured by Audi AG's private subsidiary company manufacturing high performance automotive parts, Audi Sport GmbH (formerly quattro GmbH), and is based on the Lamborghini Gallardo and presently the Huracán platform. The fundamental construction of the R8 is based on the Audi Space Frame, and uses an aluminium monocoque which is built using space frame principles. The car is built by Audi Sport GmbH in a newly renovated factory at Audi's 'aluminium site' at Neckarsulm in Germany.It is also the first production car with full-LED headlamps.Belt and Road Initiative
The Belt and Road Initiative (BRI) is a global development strategy adopted by the Chinese government involving infrastructure development and investments in 152 countries and international organizations in Asia, Europe, Africa, the Middle East, and the Americas.
"Belt" refers to the overland routes for road and rail transportation, called "the Silk Road Economic Belt"; whereas "road" refers to the sea routes, or the 21st Century Maritime Silk Road.It was known as the One Belt One Road (OBOR) (Chinese: 一带一路) and the Silk Road Economic Belt and the 21st-century Maritime Silk Road (Chinese: 丝绸之路经济带和21世纪海上丝绸之路) until 2016 when the Chinese government considered the emphasis on the word "one" was prone to misinterpretation.The Chinese government calls the initiative "a bid to enhance regional connectivity and embrace a brighter future". Some observers see it as a push for Chinese dominance in global affairs with a China-centered trading network. The project has a targeted completion date of 2049, which coincides with the 100th anniversary of the People's Republic of China.Bridge
A bridge is a structure built to span a physical obstacle, such as a body of water, valley, or road, without closing the way underneath. It is constructed for the purpose of providing passage over the obstacle, usually something that can be detrimental to cross otherwise. There are many different designs that each serve a particular purpose and apply to different situations. Designs of bridges vary depending on the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it.
Most likely the earliest bridges were fallen trees and stepping stones, while Neolithic people built boardwalk bridges across marshland. The Arkadiko Bridge dating from the 13th century BC, in the Peloponnese, in southern Greece is one of the oldest arch bridges still in existence and use.Controlled-access highway
A controlled-access highway is a type of highway which has been designed for high-speed vehicular traffic, with all traffic flow ingress- and egress-regulated. Common English terms are freeway (in Australia, South Africa, United States and Canada), motorway (in the United Kingdom, Pakistan, Ireland, New Zealand and parts of Australia) and expressway (parts of Canada, parts of the United States, India and many other Asian countries). Other similar terms include Interstate (in the United States) and parkway. Some of these may be limited-access highways, although this term can also refer to a class of highway with somewhat less isolation from other traffic.
In countries following the Vienna convention, the motorway qualification implies that walking and parking are forbidden, and they are reserved for the use of motorized vehicles only.
A controlled-access highway provides an unhindered flow of traffic, with no traffic signals, intersections or property access. They are free of any at-grade crossings with other roads, railways, or pedestrian paths, which are instead carried by overpasses and underpasses. Entrances and exits to the highway are provided at interchanges by slip roads (ramps), which allow for speed changes between the highway and arterials and collector roads. On the controlled-access highway, opposing directions of travel are generally separated by a median strip or central reservation containing a traffic barrier or grass. Elimination of conflicts with other directions of traffic dramatically improves safety and capacity.
Controlled-access highways evolved during the first half of the 20th century. Italy opened its first autostrada in 1924, A8, connecting Milan to Varese. Germany began to build its first controlled-access autobahn without speed limits (30-kilometre (19 mi) on what is now A555, then referred to as a dual highway) in 1932 between Cologne and Bonn. It then rapidly constructed a nationwide system of such roads. The first North American freeways (known as parkways) opened in the New York City area in the 1920s. Britain, heavily influenced by the railways, did not build its first motorway, the Preston By-pass (M6), until 1958.
Most technologically advanced nations feature an extensive network of freeways or motorways to provide high-capacity urban travel, or high-speed rural travel, or both. Many have a national-level or even international-level (e.g. European E route) system of route numbering.Grand Prix motorcycle racing
Grand Prix motorcycle racing refers to the premier class of motorcycle road racing events held on road circuits sanctioned by FIM. Independent motorcycle racing events have been held since the start of the twentieth century and large national events were often given the title Grand Prix, The foundation of a recognised international governing body for motorcycle sport, the Fédération Internationale de Motocyclisme in 1949 provided the opportunity to coordinate rules and regulations in order that selected events could count towards official World Championships as FIM Road Racing World Championship Grand Prix. It is the oldest established motorsport world championship.Grand Prix motorcycles are purpose-built racing machines that are generally unavailable for purchase by the general public or able to be ridden legally on public roads. This contrasts with the various production-based categories of racing, such as the Superbike World Championship and the Isle of Man TT Races that feature modified versions of road-going motorcycles available to the public.
The championship is currently divided into four classes: Moto General Practitioner, Moto2, Moto3 and MotoE. The first three classes use four-stroke engines, while the MotoE class (new in 2019) uses electric motors. The 2019 MotoGP season comprises 19 Grands Prix, with 12 held in Europe, three in Asia, two in the Americas, and one each in Australia and the Middle East.Highway
A highway is any public or private road or other public way on land. It is used for major roads, but also includes other public roads and public tracks: It is not an equivalent term to controlled-access highway, or a translation for autobahn, autoroute, etc.
According to Merriam Webster, the use of the term predates 12th century. According to Etymonline, "high" is in the sense of "main".
In North American and Australian English, major roads such as controlled-access highways or arterial roads are often state highways (Canada: provincial highways). Other roads may be designated "county highways" in the US and Ontario. These classifications refer to the level of government (state, provincial, county) that maintains the roadway.
In British English, "highway" is primarily a legal term. Everyday use normally implies roads, while the legal use covers any route or path with a public right of access, including footpaths etc.
The term has led to several related derived terms, including highway system, highway code, highway patrol and highwayman.Interchange (road)
In the field of road transport, an interchange is a road junction that uses grade separation, and typically one or more ramps, to permit traffic on at least one highway to pass through the junction without interruption from other crossing traffic streams. It differs from a standard intersection, where roads cross at grade. Interchanges are almost always used when at least one road is a controlled-access highway (freeway or motorway) or a limited-access divided highway (expressway), though they are sometimes used at junctions between surface streets.Karachi
Karachi (Urdu: کراچی; ALA-LC: Karācī, IPA: [kəˈraːtʃi] (listen); Sindhi: ڪراچي) is the capital of the Pakistani province of Sindh. It is the most populous city in Pakistan, and sixth-most-populous city proper in the world. Ranked as a beta-global city, the city is Pakistan's premier industrial and financial centre and is considered as the cultural, economic, philanthropic, educational, and political hub of the country. Karachi is also Pakistan's most cosmopolitan city. Situated on the Arabian Sea, Karachi serves as a transport hub, and is home to Pakistan's two largest seaports, the Port of Karachi and Port Bin Qasim, as well as Pakistan's busiest airport, Jinnah International Airport.
Though the Karachi region has been inhabited for millennia, the city was founded as the fortified village of Kolachi in 1729. The settlement drastically increased in importance with the arrival of British East India Company in the mid 19th century, who not only embarked on major works to transform the city into a major seaport, but also connected it with their extensive railway network. By the time of the Partition of British India, the city was the largest in Sindh with an estimated population of 400,000. Following the independence of Pakistan, the city's population increased dramatically with the arrival of millions of Muslim refugees from India. The city experienced rapid economic growth following independence, attracting migrants from throughout Pakistan and South Asia. Karachi is one of Pakistan's most secular and socially liberal cities. It is also the most linguistically, ethnically, and religiously diverse city in Pakistan. Karachi’s population was enumerated at 14.9 million in the 2017 census. Karachi is one of the world's fastest growing cities, and has communities representing almost every ethnic group in Pakistan. Karachi is home to over 2 million Bangladeshi immigrants, 1 million Afghan refugees, and up to 400,000 Rohingyas from Myanmar.Karachi is now Pakistan's premier industrial and financial centre. The city has a formal economy estimated to be worth $113 billion as of 2014 which is the largest in Pakistan. Karachi collects over a third of Pakistan's tax revenue, and generates approximately 20% of Pakistan's GDP. Approximately 30% of Pakistani industrial output is from Karachi, while Karachi's ports handle approximately 95% of Pakistan's foreign trade. Approximately 90% of the multinational corporations operating in Pakistan are headquartered in Karachi. Karachi is considered to be Pakistan’s fashion capital, and has hosted the annual Karachi Fashion Week since 2009.Left- and right-hand traffic
Left-hand traffic (LHT) and right-hand traffic (RHT) are the practice, in bidirectional traffic, of keeping to the left side or to the right side of the road, respectively. A fundamental element to traffic flow, it is sometimes referred to as the rule of the road.RHT is used in 165 countries and territories, with the remaining 75 countries and territories using LHT. Countries that use LHT account for about a sixth of the world's area with about 35% of its population and a quarter of its roads. In 1919, 104 of the world's territories were LHT and an equal number were RHT. From 1919 to 1986, 34 of the LHT territories switched to RHT.Many LHT countries were formerly part of the British Empire, although some were not, such as Japan, Thailand, Indonesia, and Suriname. Conversely, many RHT countries were part of the French colonial empire.For rail transport, LHT predominates in Western Europe (except Germany, Denmark, Austria, Spain, and the Netherlands), Latin America (except Mexico), and in countries formerly in the British and French Empires, whereas North American and central and eastern European train services operate RHT.
According to the International Regulations for Preventing Collisions at Sea, water traffic is effectively RHT: a vessel proceeding along a narrow channel must keep to starboard (the right-hand side), and when two power-driven vessels are meeting head-on both must alter course to starboard also. For aircraft the US Federal Aviation Regulations suggest RHT principles, both in the air and on water.In LHT vehicles keep left, and cars are RHD (right-hand drive) with the steering wheel on the right-hand side and the driver sitting on the offside or side closest to the center of the road. The passenger sits on the nearside, closest to the curb. Roundabouts circulate clockwise. In RHT everything is reversed: cars keep right, the driver sits on the left side of the car, and roundabouts circulate counterclockwise.Lil Nas X
Lil Nas X (born April 9, 1999 as Montero Lamar Hill) is an American rapper, singer, and songwriter. He came to international attention for his country rap breakout single "Old Town Road", which achieved viral popularity on the video sharing app TikTok in early 2019. The song was controversially removed from the Hot Country Songs chart after debuting at nineteen, but reached the top spot on the Billboard Hot 100. At week thirteen at the top, it became the longest-running hip hop song on the chart, as of July 2019, it has remained there fifteen weeks, making him the only openly gay artist to do so. His debut EP, 7, was released on June 21, 2019. His second single from 7, "Panini", also remains in the top ten after debuting there July 3, 2019.Old Town Road
"Old Town Road" is a song by American rapper Lil Nas X. It was initially released independently on December 3, 2018, and gained popularity on social video sharing app TikTok. As a result, Lil Nas X was signed to Columbia Records, which now distributes the single. The song was produced by YoungKio and features a sample of the instrumental piece "34 Ghosts IV" by Nine Inch Nails, with the band members receiving songwriting and production credits. A remix of the song featuring Billy Ray Cyrus was released on April 5, 2019. A second remix of the song featuring Billy Ray Cyrus and Diplo was released on April 29, 2019. Another remix featuring American rapper Young Thug and American singer Mason Ramsey was released on July 12, 2019. It was included alongside its remix on Lil Nas X's debut EP, 7.
In March 2019, the song reached number 19 on the Billboard Hot Country Songs chart before the magazine disqualified it from being included on the chart on grounds that it did not fit the country genre, sparking a debate on the definition of the genre. Had it not been disqualified, "Old Town Road" would have been the Hot Country Songs number-one song, as of the chart dated April 6, 2019.Though the song was not re-entered onto the overall country charts, both the original version of the song and the remix featuring Billy Ray Cyrus eventually peaked at number one on the flagship Billboard chart, the Hot 100, for a consecutive fifteen weeks. The song was the first-ever number-one song on the Rolling Stone Top 100 chart. Internationally, one or more versions of "Old Town Road" have topped the national singles charts in Australia, Canada, France, Germany, Ireland, the Netherlands, New Zealand, Norway, Switzerland, and the United Kingdom; and charted within the top ten in various other markets.
At one minute and fifty-three seconds in length, the original version of "Old Town Road" is the fifth-shortest number-one single in the history of the Billboard Hot 100, and the shortest since 1965.Road to Perdition
Road to Perdition is a 2002 American crime film directed by Sam Mendes. The screenplay was adapted by David Self from the graphic novel of the same name by Max Allan Collins. The film stars Tom Hanks, Paul Newman, Jude Law, and Daniel Craig. The plot takes place in 1931, during the Great Depression, following a mob enforcer and his son as they seek vengeance against a mobster who murdered the rest of their family.
Filming took place in the Chicago area. Mendes, having recently finished 1999's acclaimed American Beauty, pursued a story that had minimal dialogue and conveyed emotion in the imagery. Cinematographer Conrad L. Hall took advantage of the environment to create symbolism for the film, for which he won several awards, including a posthumous Academy Award for Best Cinematography. The film explores several themes, including the consequence of violence and father-son relationships.
The film was released on July 12, 2002, and eventually grossed over $180 million worldwide. The cinematography, setting, and the lead performances by Hanks and Newman were well received by critics. It was released on home media on February 25, 2003.Silk Road
The Silk Road was a network of trade routes which connected the East and West, and was central to the economic, cultural, political, and religious interactions between these regions from the 2nd century BCE to the 18th century. The Silk Road primarily refers to the terrestrial routes connecting East Asia and Southeast Asia with South Asia, Persia, the Arabian Peninsula, East Africa and Southern Europe.
The Silk Road derives its name from the lucrative trade in silk carried out along its length, beginning in the Han dynasty in China (207 BCE–220 CE). The Han dynasty expanded the Central Asian section of the trade routes around 114 BCE through the missions and explorations of the Chinese imperial envoy Zhang Qian, as well as several military conquests. The Chinese took great interest in the security of their trade products, and extended the Great Wall of China to ensure the protection of the trade route.The Silk Road trade played a significant role in the development of the civilizations of China, Korea, Japan, the Indian subcontinent, Iran, Europe, the Horn of Africa and Arabia, opening long-distance political and economic relations between the civilizations. Though silk was the major trade item exported from China, many other goods and ideas were exchanged, including religions (especially Buddhism), syncretic philosophies, sciences, and technologies like paper and gunpowder. So in addition to economic trade, the Silk Road was a route for cultural trade among the civilizations along its network. Diseases, most notably plague, also spread along the Silk Road.In June 2014, UNESCO designated the Chang'an-Tianshan corridor of the Silk Road as a World Heritage Site. The Indian portion is on the tentative site list.Sodium chloride
Sodium chloride , commonly known as salt (though sea salt also contains other chemical salts), is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35.45 g/mol respectively, 100 g of NaCl contains 39.34 g Na and 60.66 g Cl. Sodium chloride is the salt most responsible for the salinity of seawater and of the extracellular fluid of many multicellular organisms. In its edible form of table salt, it is commonly used as a condiment and food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further chemical syntheses. A second major application of sodium chloride is de-icing of roadways in sub-freezing weather.Traffic collision
A traffic collision, also called a motor vehicle collision (MVC) among other terms, occurs when a vehicle collides with another vehicle, pedestrian, animal, road debris, or other stationary obstruction, such as a tree, pole or building. Traffic collisions often result in injury, death, and property damage.
A number of factors contribute to the risk of collision, including vehicle design, speed of operation, road design, road environment, and driver skill, impairment due to alcohol or drugs, and behavior, notably distracted driving, speeding and street racing. Worldwide, motor vehicle collisions lead to death and disability as well as financial costs to both society and the individuals involved.
In 2013, 54 million people worldwide sustained injuries from traffic collisions. This resulted in 1.4 million deaths in 2013, up from 1.1 million deaths in 1990. About 68,000 of these occurred in children less than five years old. Almost all high-income countries have decreasing death rates, while the majority of low-income countries have increasing death rates due to traffic collisions. Middle-income countries have the highest rate with 20 deaths per 100,000 inhabitants, accounting for 80% of all road fatalities with 52% of all vehicles. While the death rate in Africa is the highest (24.1 per 100,000 inhabitants), the lowest rate is to be found in Europe (10.3 per 100,000 inhabitants).U.S. Route 66
U.S. Route 66 or U.S. Highway 66 (US 66 or Route 66), also known as the Will Rogers Highway, the Main Street of America or the Mother Road, was one of the original highways in the U.S. Highway System. US 66 was established on November 11, 1926, with road signs erected the following year. The highway, which became one of the most famous roads in the United States, originally ran from Chicago, Illinois, through Missouri, Kansas, Oklahoma, Texas, New Mexico, and Arizona before ending in Santa Monica in Los Angeles County, California, covering a total of 2,448 miles (3,940 km). It was recognized in popular culture by both the hit song "(Get Your Kicks on) Route 66" and the Route 66 television series, which aired on CBS from 1960 to 1964. In John Steinbeck's classic American novel, The Grapes of Wrath (1939), the road, "Highway 66", was turned into a powerful symbol of escape and loss.
US 66 served as a primary route for those who migrated west, especially during the Dust Bowl of the 1930s, and the road supported the economies of the communities through which it passed. People doing business along the route became prosperous due to the growing popularity of the highway, and those same people later fought to keep the highway alive in the face of the growing threat of being bypassed by the new Interstate Highway System.
US 66 underwent many improvements and realignments over its lifetime, but was officially removed from the United States Highway System in 1985 after it had been replaced in its entirety by segments of the Interstate Highway System. Portions of the road that passed through Illinois, Missouri, New Mexico, and Arizona have been communally designated a National Scenic Byway of the name "Historic Route 66", returning the name to some maps. Several states have adopted significant bypassed sections of the former US 66 into their state road networks as State Route 66. The corridor is also being redeveloped into U.S. Bicycle Route 66, a part of the United States Bicycle Route System that was developed in the 2010s.
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