Mam Tor

Mam Tor is a 517 m hill near Castleton in the High Peak of Derbyshire, England. Its name means "mother hill", so called because frequent landslips on its eastern face have resulted in a multitude of "mini-hills" beneath it. These landslips, which are caused by unstable lower layers of shale, also give the hill its alternative name of Shivering Mountain.

In 1979, the continual battle to maintain the A625 road on the crumbling eastern side of the hill was lost when the road officially closed as a through-route, with the Fox House to Castleton section of the road being re-designated as the A6187.