Читать книгу Walks in Silverdale and Arnside. 21 easy walks exploring the AONB онлайн

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During the last Ice Age many limestone boulders were moved and deposited on other limestone beds, and there are many examples of these perched boulders, or erratics, in the area. (They are so called because they are not derived from the rock upon which they lie.) Sometimes the ice moved rocks from further afield before depositing them; Shap granite erratics can be seen on some of the walks.

In geological time the limestone was covered by beds of red sandstone, long since removed by erosion. An interesting feature that developed at this time was caused by water seeping through the sandstone and becoming impregnated with minerals which were then deposited in the limestone caves below. This is explains the presence of copper and haematite (iron ore) which were mined in several parts of the area, especially at Crag Foot, where layers of brecciated sandstone filled the phreatic passages.

Karren grooves at The Rakes (Walks 16, 18)

Industry through the ages

Early settlers

The earliest settlers chose the well-drained terraces of Warton Crag, close to springs of good water. Dog Holes, above Crag Foot on Warton Crag, is archaeo-logically interesting but there is no public access. At the foot of a small shaft there are several galleries which have yielded a rich collection of remains, the earliest dating from Late Pleistocene times. Beaker-ware, flints and human remains from Neolithic times, Bronze Age pans and enamelled bronze-work and Roman pottery have all been recovered. It seems that the cave was used for human habitation over a very long period of time. Other archaeological remains have been found at another Dog Holes, on Haverbrack, but not in the same quantity as at Warton.