Banwell Bone Cave is quite remarkable. The cave holds thousands and thousands of prehistoric animal bones, about 60,000 years old, washed in there when glaciers melted.
The site also contains a number of beautifully renovated follies, originally built in the 1820s when the cave was discovered and put on display to the public. The two-and-a half hour tour (includes a short film) ends with tea and cakes with the owners.
The caves are on private land and only open to the public very infrequently. Tuesday 27 Sept will be the last time this year as greater horseshoe bats hibernate there, so they don't open again till May next year.
If you are interested, please contact one of the owners, John Haynes
firstname.lastname@example.org for details.