http://webapp1.somerset.gov.uk/her/details.asp?prn=33283

The Longstone.

"An upright standing stone, of probably local material, set very firmly in the ground on the parish boundary between Kilve and East Quantoxhead at the end of Longstone Hill. On the NE side of the stone there is a small circular depression which may not be a natural feature - possibly a cup mark which would suggest a Bronze Age origin for the stone. "

Wish I'd seen that before I was about 20 miles away from it on Sunday...