Abergynolwyn (English: Mouth of the River with a Whirlpool) is a village in southern Gwynedd, Wales, located at the confluence of the Nant Gwernol and the Afon Dysynni.

The quarry brought in migrant workers from other areas of Wales and at one time the village had an Anglican church and three nonconformist chapels.

A decline in the demand for Welsh slate caused reductions in the workforce, and the quarry finally closed in 1948.

[3] The village is situated on the B4405 road, which passes through the centre, and is served by the G24 bus route.

The Iron Age fort on Craig yr Aderyn shows that the area was strategically important in prehistoric times.