thesweetcheat wrote:
It's not volcanic rock. The geology is primarily limestone, and was presumably a sea bed at one time. It has probably been cut off from the main body of the nearby Cotswold escarpment by water wearing away surrounding clays (as the water sinks through the limestone level but washes clay away). So rather than being thrust upwards (by a volcano), the surrounding land has been worn down, leaving the conical hill behind.
The Hole of Horcum in Yorkshire which looks as if it has been hit by an asteroid is in fact created by the drip, drip of water over the millenia.Often wondered about Bath which is also encircled by hills giving it a bowl shape, whether that was volcanic, especially given the hot waters there.
