The 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.
Archaeological excavations have taken place in 1936/1937 and 1958/1959, both led by William Francis Grimes.
- www.geograph.co.uk : photos of Pentre Ifan and surrounding area
- The best preserved megalithic site in Wales - Extrageographic