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. Winnats Pass is a hill pass and limestone gorge in the Peak District of Derbyshire, England. The name is a corruption of 'wind gates' due to the swirling winds through the pass. It lies west of the village of Castleton, in the National Trust's High Peak Estate and the High Peak borough of Derbyshire.