Kents Cavern is a fascinating attraction for all members of the family. It is the oldest inhabited dwelling with it being used for over 700,000 years continuously. Many objects have been found to back up this claim, including an axe 450,000 years old and a human jaw bone over 31,000. It is an easy walk through the caves, with the newtork being relatively on the level. Kents Cavern is considered one of the most important palentogolgy sites in Europe.
The cavern is open daily from 10:00 to 16:30, with tours running throughout the day, admission is £6.50, under 4s free. There is of course a cafe and shop here too.
Their web site below is excellent for more information.