Pentre Ifan burial chamberThe dolmen dates from approximately 3,500 B.C. and, possibly, was used as a communal burial. The existing stones form the portal and main chamber of the tomb, which would originally have been covered with a large stone mound about 36.6 m long and 17 m wide. Some of the stones have been scattered, but at least seven are in their original position. The capstone is 5.1 m in length, and is estimated to weigh 16 tonnes, and rises 2.4 m above the ground. It is delicately supported by the narrow tips of three uprights. The facade surrounding the portal was built with carefully constructed dry stone walling.(wiki)
It's free to see and open at all hours.Just push the little gate and enter. This time of year, there is not a soul around. Just the occasional local, walking the dog. Great place to visit.