Skye that requires technical climbing skills to reach the summit. These hills make demands of the hill walker that exceed any others found in Scotland and a full traverse of the Cuillin ridge may take 15–20 hours. The Red Hills (Gaelic: ) to the south are also known as the Red Cuillin. They are mainly composed of granite that has weathered into more rounded hills with many long scree slopes on their flanks. The highest point of these hills is Glamaig, one of only two Corbetts on Skye. The northern peninsula of Trotternish is underlain by basalt, which provides relatively rich
Cuillin the summits had no recorded name prior to this period, although names for corries and other features were in existence. Many of the summits are thus named after early climbers such as John MacKenzie (Sgùrr MhicChoinnich), Alexander Nicolson (Sgùrr Alasdair), and Norman Collie (Sgúrr Thormaid). The Cuillin now consists of two estates divided by Glen Sligachan. The hills on the west side of Glen Sligachan (the Black Cuillin) remained the property of Clan MacLeod despite the long history of conflict between them and Clan MacDonald. The earliest formal record of MacLeod ownership was in a land grant from the Crown