Читать книгу Walking in the Yorkshire Dales: South and West. Wharfedale, Littondale, Malhamdale, Dentdale and Ribblesdale онлайн

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Heading into Trow Gill (Walk 41)

Also composed of limestone, although of a different formation to the Great Scar, is a striking line of small hills between Malham and Grassington. Termed reef knolls, they are the remnants of a coral barrier reef that marked the edge of a shelf in the shallow sea. Erosion of the later, overlying softer deposits has revealed these submarine hillocks once more, distinctive because of their conical shape.

Away from the Great Scar, the scenery is no less stirring – a great plateau of high ground fragmented by deep valleys to create long, broad-backed ridges. The level bedding of the rocks has resulted in an almost uniform height at around 610m, with just a few mountain tops daring to poke their flat heads above the rest. Most famous amongst these are the Yorkshire Three Peaks – Whernside, Ingleborough and Pen-y-ghent – planted well apart around the head of Ribblesdale. Although not one of the Dales peaks culminates in a dramatic pinnacle summit, their flanks climb steeply out of the surrounding valleys, rising in terraces through the Yoredale Series. Alternating bands of springy grass and lines of sink holes, heather heath, and then marsh reflect the nature of the changing geology underfoot, culminating in an undulating upland bog held upon the sandstones and gritstones capping the northern hills. It is this layering too that is responsible for the impressive waterfalls in Wensleydale, in particular the falls on the River Ure at Aysgarth and the great cascade of Hardraw Force above Hawes.