Mam Tor Iron Age fort overlooking Castleton and Hope Valley, Derbyshire

Mam Tor is a famous viewpoint and landmark, rearing up above the valleys of Hope and Edale. Known as the 'shivering mountain', it is comprised of shale and the East face is a dramatic and loose expanse of crumbling rock. The area below the face is constantly on the move and each period of heavy rain undermines the loose shale and causes it to slip further down the valley. The former A625 main road from Stockport to Sheffield once went down this way but was swept away by a landslide in 1974 and has not been rebuilt.

On the top of the hill was a large Iron Age fort, and the fortifications can still be seen. However, the site was almost certainly occupied long before this. The trig point on the summit of the hill is placed on top of a tumulus which probably dates from the Bronze Age, and a bronze axehead has also been found here. Unfortunately the tumulus is now hard to make out because erosion has forced the National Trust, who own the hill and the nearby Winnats Pass, to pave the summit area.

The ramparts can be followed most of the way around the hilltop, and there are clear remains of two gateways on the paths leading from Mam Nick and from Hollins Cross. Excavations have shown that the original ramparts had a timber pallisade on top, but later the timber was replaced by stone. There are also the foundations of many hut circles within the defences and pottery has also been found, which indicates that this was a fully-fledged village rather than just a defensive site.

The views from the summit of Mam Tor are superb, with a fine view of Edale and Kinder to the north and Hope valley to the east, and a splendid ridge leading from the summit down to Hollins Cross and along to Lose Hill. Mam Tor looks particularly impressive when approached across the limestone moors from the direction of Peak Forest.

The escarpments around Mam Tor and nearby Lord's Seat and Rushup Edge seem to attract winds at all times and this has led to it becoming the most popular local centre for hang-gliding and paragliding.