The Mam Tor Landslip

A general view of the old Mam Tor road

During August 2017, the trip to Hope Cement Works with the Sheffield U3A Geology Group provided me with an opportunity to visit a place that I was otherwise unlikely to see; however, the afternoon session was dedicated to a brief exploration of the landslips at the base of Mam Tor – a site that I first visited as an undergraduate geologist and have seen many times since when visiting Castleton for both work and pleasure. 

Mam Tor with the entrance to the old Odin Mine in the foreground

The vertical faced scar exposes a cyclical succession of turbidite sandstones and shale of the Mam Tor Beds, which are very susceptible to landslips and has resulted in Mam Tor also being known as the shivering mountain. 

The Mam Tor landslip

Elsewhere in the Dark Peak – such as the nearby Back Tor and Bretton Clough – there are other spectacular examples of landslips but, at Mam Tor, it is the history of the failed attempts to keep the A625 road open that is of most interest here. 

A view across the landslip towards Castleton

Mam Tor road was first constructed across the landslip zone in 1819 using spoil from the nearby Odin Mine, to replace an ancient packhorse route that ran through Winnats Pass. This rotational landslide, which began approximately 4000 years ago, is particularly active after periods of prolonged wet weather and major road works were undertaken several times during the 20th century until 1979, when it was finally closed. 

A general view of the Mam Tor road

When I first visited Mam Tor, I remember that the recently closed A625 road wasn’t in very good condition but, nearly 40 years later, I was extremely surprised to see how much it had deteriorated - large sections of the old road have been fractured and others have broken up completely have been slowly sliding down the slope. 

A view of Hope Cement Works with Castleton in the foreground

As with the visit to Hope Cement Works earlier in the day, memories of studying Industrial and Environmental Geology as an undergraduate came flooding back. My 2: II Bsc. Hons. degree in Geology, with subsidiary Chemistry and Zoology, is nothing to boast about; however, on this course, I was top of my class and it proved to be influential on future work that I would do. 

Fractures on the old Mam Tor road

Although by no means an expert on the construction of roads, I think that students of engineering geology and civil engineering would find the remains of the Mam Tor road particularly fascinating. Sections up to 2 metres thick, exposing the various road courses, record the numerous efforts to keep this very important road route open over the years. 

A section through the old Mam Tor road

The geology, mineralogy, geomorphology, archaeology, industrial history and beauty of Castleton and the surrounding area ensure that it ranks very highly in the places to visit in the Peak District National Park - for geologists and the general public alike. 

A general view of the old Mam Tor road