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).
Lists of mountains and hills in the British Isles the concept of isolation is embedded in the "qualitative" definition of a Scottish Munro, from the Scottish Mountaineering Club requirement of "sufficient separation" (instead of prominence). Mountains in Scotland are frequently referred to as "hills" no matter what their height, as reflected in names such as the "Cuillin Hills" and the "Torridon Hills". The "Database of British and Irish Hills" ("DoBIH") was created in 2001 "with the intention of providing a comprehensive, up-to-date resource for British hillwalkers". It is now maintained by a team of eight editors, and is described by the Long Distance Walkers Association as "now the most