It lies within the valley of the Taf Fechan on the southern edge of the Brecon Beacons National Park.
[1] The village lies within the community of Vaynor in an area that was, until the local government re-organisation of 1974, within the historic county of Brecknockshire.
The village name originates from the Welsh words pont and sticill and signifies a 'bridge near a stile'.
[3] To the north of Pontsticill and to the east of the reservoir, lie Abercriban Quarries, a Site of Special Scientific Interest.
The site is of special interest for the rock exposures of the Grey Grit Formation of the Upper Old Red Sandstone; these exposed rocks span the boundary between the Carboniferous and Devonian periods of geological time, approximately 360 million years ago.