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
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