One of the many barrows at Came Wood yielded a rare (for the South of England) example of prehistoric rock art in the form of a cist cover with three concentric circles. It gets a mention in Tate’s ‘Sculptured rocks’ book, a more detailed description being given by the excavator. (Warne, C. 1866. The Celtic Tumuli of Dorset. London: John Russell Smith.)
An image of the concentric circles can be found on the University College London web site.
Alas, this particular marked stone is currently on the missing list.