Lanhill Long Barrow is a Neolithic long barrow ( Burial Chamber) with the chamber on the north side. It was opened by John Thurnam in 1855, and partially excavated in 1909 and in 1936.
Orientated East / West, it was originally about 190 feet long and 90 feet wide. There are two small burial chambers, one on the north side, the other one visible on the south, with maybe a false entrance on the east end.
Apparently 20 burials were found in the chambers and evidence from the bones suggest that it was used by one family.
Taken from A Guide to Prehistoric England - Nicholas Thomas.
There is a visible entrance to the Barrow ( see Photo) found at N51.28.272 W 002.10.683
Take a few moments to enjoy the atmosphere here.