Mountains and hills of Scotland near Ullapool and Stac Polly in Sutherland. The Torridonian rocks continue south to Applecross opposite Skye, where similar massive mountains occur. The Black Cuillin are mainly composed of basalt and gabbro, the latter being a very rough rock which makes for superb grip for mountaineers. It is from the dark colour of the gabbro that the Black Cuillin receive their name. The summits of the Cuillin are bare rock, jagged in outline and with steep cliffs and deep cut corries and gullies. The mountains exhibit many notable individual peaks and many exceed 1,000 metres (3,280 ft) in height, so qualifying
Cuillin Celtic mythology, with the hills being the place where Cuchullin learnt archery from the female warrior Scáthach. It is also suggested that the derivation of the name may reflect the "worthless" (in an agricultural or economic sense) nature of the hills, given their lack of vegetation. The Cuillin are a diverse and complex geological landscape, and there is a clear distinction visible between the two mountain types. The mountains formed from the remains of the magma chambers which fed volcanic eruptions. In the Black Cuillin the rocks cooled to form gabbro, the coarse-grained rock that makes up much of the