It follows a section of the former Manchester, Buxton, Matlock and Midlands Junction Railway, built by the Midland Railway in 1863 to link Manchester with London. The line was closed in 1968 by the Labour Minister for Transport Barbara Castle, not as it is often thought by the Beeching Axe, and remained unused for twelve years before being taken over by the Peak District National Park.
The Monsal Trail is about 8.5 miles (13.7 km) in length and opened in 1981. It starts at the Topley Pike junction (in Wye Dale, 3 miles (4.8 km) east of Buxton) and runs to Coombs Viaduct, 1 mile (1.6 km) south-east of Bakewell. It follows the valley of the River Wye and runs parallel to the A6.
From the Wyedale car park, the easiest access point for the northern end of the trail, there is a walk of about 1 kilometre (0.62 mi), with the last part up steps, to reach the trail. Starting at the south of the trail, "from Market Place in Bakewell, follow Sheffield Road and cross the five-arched bridge of the River Wye, turn right and ascend Station Road to the former Bakewell railway station and car park on your left."
The trail passes through such places as Blackwell Mill, Millers Dale, Cressbrook, Monsal Dale, Great Longstone, Hassop and Bakewell. In the cases of Longstone and Hassop, although railway stations were provided, they were some distance from the villages.
This route through the Wye valley was necessitated by the Duke of Devonshire's objection to the railway passing through his grounds (which included not only Chatsworth House, but extensive grounds north of Rowsley). This route meant, for instance, that the line had to pass above the town of Bakewell, rather than through it.
The Duke of Rutland, of Haddon Hall, insisted on the construction of Haddon Tunnel to hide it from his view, but he used Bakewell railway station, which was built to a grander design than normal, and carried his coat of arms.
The Duke of Devonshire later came to realise the value of the railway, and his offer for the Midland Railway to run through Chatsworth came too late. He was therefore the force behind the construction of Hassop railway station, which, although nearer to Bakewell than Hassop village itself, meant that he did not have to share a railway station with his neighbour, the Duke of Rutland.
Great Longstone (simply called 'Longstone' before 1913) served Thornbridge Hall, and the railway station design, with leaded glass windows, reflected the architecture of the hall itself.
For many years the trail could not follow the trackbed throughout as tunnels had been closed for safety reasons, such as at Monsal Head and Cressbrook, meaning that the trail was diverted. The tunnels were walked by Julia Bradbury as part of BBC TV's Railway Walks: The Peak Express. Many resulting access points and diversion paths were unsuitable for those using cycles or wheelchairs or with difficulty walking due to steep uneven stone steps or narrow paths. Plans to make the tunnels safe and re-open them to the public were given the go-ahead at a cost of £3.785m, and the tunnels were opened officially for use on 25 May 2011 at a ceremony at the Headstone Viaduct (they had been open for use since 13 May 2011). As a consequence, the trail is now virtually level (though the former diversions are still usable, if desired), and can thus be used by wheelchair users with level access onto the trail at Bakewell, Hassop railway station (disabled toilets at Bakewell and Millers Dale railway stations) and Millers Dale.
The notorious Litton Mill, downstream from Millers Dale railway station, is where orphans from major cities were abused by Ellis Needham, with the graves of many to be found in local churchyards. William Newton's 1783 Cressbrook Mill (on the site of a herb distillery) was used by Richard Arkwright.
Derbyshire County Council support the creation of a circular cycle route linking Buxton, Bakewell and Matlock with the High Peak Trail. Dubbed the White Peak Loop, it includes extending the Monsal Trail to Matlock, a proposal which received strong support from a public consultation exercise in 2014. The 5 mile (8 km) section between Rowsley and Matlock duly opened in March 2018, running adjacent to the railway trackbed except for minor diversions just north of Rowsley South, at Darley Dale, and at Matlock. The remaining 2.5 mile (4 km) section of the route between Bakewell (Coombs Viaduct) and Rowsley is still at the design stage. When complete the section will run for the most part along the railway trackbed and include the building of new bridges at Rowsley and the refurbishment and opening up of the 1-km Haddon Tunnel.
Headstone Viaduct, at Monsal Head, is one of the more impressive structures on the line, although when it was built it was seen as destroying the beauty of the dale. John Ruskin, a poet and conservationist of the time, criticised the folly of building the railway:
His words are displayed on the viaduct. However, when the railway closed and there was talk of demolishing the viaduct, there was considerable opposition. In 1970 a preservation order was placed on the structure.
Equally impressive, though less easily viewed, are the twin viaducts at Millers Dale, from where a branch line ran to Buxton. The trail runs across the older of the two.
The trail passes through the following tunnels: