Читать книгу The Isle of Skye. Graded walks and scrambles throughout Skye, including the Cuillin онлайн

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The most dramatic scenery, however, is formed from Lower Tertiary intrusive rocks, of which gabbro and granite are the most significant. It is from these rocks that the Cuillin are formed, and the distinction between these rocks and the intrusive acid rocks of the Red Hills is most noticeable as you walk through Glen Sligachan.

During the Tertiary period many parts of Skye were subjected to massive volcanic activity, probably the most violent in Britain. To the north-west of Kilchrist you can still see the vent of an ancient volcano; it has a diameter of about 5km (3 miles). When all that ceased, the island enjoyed about 50 million years of relative calm, until the ice came. The Pleistocene period, the Age of Ice, started about two million years ago, and is largely responsible for producing the landscape we see today. Massive ice sheets covered most of Britain, and huge glaciers flowed across the landscape, moving, plucking, breaking, scratching at the rocks below the ice. When finally they left, they had created a fascinating land form, one that was to be further shaped as sea levels fluctuated, forming raised beaches around Skye, and the agents of erosion got to work.