This particular swallow hole fills and drains with changing weather conditions. It is only a short distance from the minor road across the moor. Curiously there is a substantial Bronze Age cairn nearby and it seems likely that there is a connection between the two features.
Uploaded to Geograph by Alan Bowring on 1 July 2008
Photo © Alan Bowring, 1 July 2008. Licensed for reuse under this Creative Commons licence