Loch na Cuilce and Loch Coruisk with Black Cuillin in the background, Isle of Skye, Scotland

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Skye-high mountains in Scotland. Now that’s a mountain to climb

The Cuillin mountains on the beautiful Isle of Skye in Scotland are separated into two dramatic ranges which dominate the island's landscape: the Black Cuillin and the Red Cuillin. The iconic ridge of the Black Cuillin, seen in the background of our photo, was formed some 60 million years ago from the remains of the magma chambers which fed volcanic eruptions. Over 11 kilometres long, it's considered the UK's most challenging and spectacular mountain range, containing 11 Munros (a mountain in Scotland with a height over 3,000 feet) and 16 other summits. The rugged peaks of the Black Cuillin are mainly composed of gabbro, a coarse-grained rock with excellent grip for mountaineering.