Tor (rock formation)

A tor, which is also known by geomorphologists as either a castle koppie or kopje, is a large, free-standing rock outcrop that rises abruptly from the surrounding smooth and gentle slopes of a rounded hill summit or ridge crest.

In the South West of England, the term is commonly also used for the hills themselves – particularly the high points of Dartmoor in Devon and Bodmin Moor in Cornwall.

[3] Tors are landforms created by the erosion and weathering of rock; most commonly granites, but also schists, dacites, dolerites, ignimbrites,[4] coarse sandstones and others.

[7] Where joints are closely spaced, the large crystals in the granite readily disintegrate to form a sandy regolith known locally as growan.

This is readily stripped off by solifluction or surface wash when not protected by vegetation, notably during prolonged cold phases during the Quaternary ice ages – periglaciation.