Scottish Highlands in the Torridon Hills such as Liathach and Beinn Eighe in Wester Ross. These foundations are interspersed with many igneous intrusions of a more recent age, the remnants of which have formed mountain massifs such as the Cairngorms and the Cuillin of Skye. A significant exception to the above are the fossil-bearing beds of Old Red Sandstone found principally along the Moray Firth coast and partially down the Highland Boundary Fault. The Jurassic beds found in isolated locations on Skye and Applecross reflect the complex underlying geology. They are the original source of much North Sea oil. The Great Glen
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