Pentre Ifan is the name of an ancient manor in the civil parish of Nevern, in North Pembrokeshire, West Wales. It contains the largest and best preserved neolithic dolmen in Wales.

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.

The dolmen is owned and maintained by Cadw, the Welsh Historic Monuments Agency. The site is well-kept and entrance is free. It is located about 6 km by road from Newport and 17 km from Cardigan.

Coordinates: 51°39′17″N 3°29′32″W / 51.654736°N 3.492269°W / 51.654736; -3.492269

Pentre is a village and community, near Treorchy in Rhondda valley, falling within the county borough of Rhondda Cynon Taf, Wales. The village's name is taken from the Welsh word Pentref, which translates as homestead, though Pentre is named after a large farm that dominated the area before the coming of industrialisation. The community takes in the neighbouring village of Ton Pentre.

Pre-1850, the area which is now Pentre was made up of several scattered farms tended by tenant farmers for absentee landlords. With the discovery, in the early 19th century, of economically viable coal deposits in Dinas Rhondda it was not long until expeditions reached the mid valleys. In 1857 Edward Curteis of Llandaff leased the mineral rights of Tyr-y-Pentre from Griffith Llewellyn of Baglan and soon had two levels opened, the Pentre and Church. During the early part of 1864 deeper shafts had been sunk by the Pentre Coal Company. The mines in the Pentre were some of the most profitable of all the collieries in the Rhondda.