Cuillin range. Cracks and fissures in the rock provided pathways for later magma intrusions, leading to dykes of basalt which are commonly seen across Skye. The Red Cuillin also have volcanic origins, being formed from a later intrusion of acidic, granitic rock. This granite was more uniformly eroded by wind and water than the gabbro and basalt, causing the red hills to have smoother outlines. The Cuillin provide classic examples of glacial topography and were the subject of an early published account by James Forbes in 1846 (who had become a fellow of the Royal Society of Edinburgh aged only nineteen).
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