Yorkshire Three Peaks
The mountains of Whernside (736 m or 2,415 ft), Ingleborough (723 m or 2,372 ft) and Pen-y-ghent (694 m or 2,277 ft) are collectively known as the Three Peaks. The peaks, which form part of the Pennine range, encircle the heads of the valleys of the River Ribble and of Chapel-le-Dale in the Yorkshire Dales National Park in the North of England.
The long-standing designation "The Three Peaks" is well known locally, and in past times nationally. However, there are now a number of "National" Three Peaks adventure challenges involving Ben Nevis, Snowdon and Scafell Pike (respectively the highest summits in Scotland, Wales and England). The epithet "Yorkshire" is therefore now commonly added to differentiate Yorkshire's Three Peaks from those (although Whernside is partially in Cumbria, with the summit trig point being narrowly on the Cumbria side).
In common with neighbouring fells, the Three Peaks are carved from an almost flat-lying succession of sedimentary strata of Carboniferous age. The lower slopes of each of the fells are formed from massive limestones assigned to the Visean age Great Scar Group. The upper slopes of each of the fells are formed from alternating bands of limestone, and mudstone grading up into sandstone, all of which are assigned to the Brigantian and early Namurian ages Yoredale Group. These alternations are considered to be a classic British example of cyclothems. Differential weathering and erosion of the various bands has given Ingleborough and Pen-y-ghent a distinctive, stepped appearance. The summits are capped by Grassington Grit, a variety of Millstone Grit.
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