This is not a natural cave, but a hole blasted into the hillside just across the lake from the village of Rydal, probably some time in the nineteenth century. The slate from here found its way into the roofs and walls of the houses nearby. There is a half-hearted fence at the entrance, which is more of a warning than an actual obstruction. Even so, I felt a bit uneasy taking this picture because of the large boulders at the back of the cave, which had clearly fallen from the roof.
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