Scottish hills

Scotland is the most mountainous country in the United Kingdom. The area north and west of the Highland Boundary Fault is known as the Highlands, and contains the country's main mountain ranges. Scotland's mountain ranges, in a rough north to south direction are: The Highlands & Islands, The Hills of the Central Lowlands, the Southern Uplands. The zone includes Britain's highest peaks, especially Ben Nevis at over 4000 feet, with several similar peaks in the Cairngorms.

Some of the most spectacular mountains occur in the northwest highlands, especially on Skye, the largest island off the coast. On the mainland nearby lie some great ranges based on the Torridonian sandstone, a Precambrian rock which overlies yet older rocks such as the Lewisian gneiss. Some of the highest peaks, such as Beinn Eighe are crowned by white quartzite, which gives those peaks a distinctive appearance. The trend continues to the north with larger caps of the white rock at Foinaven and Arkle (hill). Some of the quartzite contains fossilized worm burrows. It is known as pipe rock and is circa 500 million years old.

The formation continues to the north with gigantic peaks such as An Teallach near Ullapool and Stac Polly in Sutherland. The Torridonian rocks continue south to Applecross opposite Skye, where similar massive mountains occur. The Black Cuillin are mainly composed of basalt and gabbro, the latter being a very rough rock which makes for superb grip for mountaineers. It is from the dark colour of the gabbro that the Black Cuillin receive their name. The summits of the Cuillin are bare rock, jagged in outline and with steep cliffs and deep cut corries and gullies.

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