What is a Glacier?

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A glacier is a large body of ice. It is formed high up in the mountains where snow falls, but never melts. As the snow accumulates, the lower layers get compressed and crushed and turn to hard ice. This begins to flow very slowly down the hill through valleys. The glaciers pick up rocks and other debris and pile them up in ridges called moraines. They move faster at the centre than at sides and this creates huge gaps or crevasses. When a glacier melts, it leaves behind lumps of polished rock surfaces, rounded hills and narrow ridges of rock debris called esters. 

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