Cemaes is a fishing port and tourist resort, and is known for its beach. It has a sheltered natural harbour that looks north to the Irish Sea and is the site of an ancient settlement. Cemaes also has a wind farm and at nearby Wylfa is a nuclear power station. The river in the village is the River Wygyr, which flows from just below Parys Mountain to the sea at Cemaes. It is joined along the way by the Afon Meddanen on Carrog Farm, Carrog. The name Wygyr is Welsh and may mean "green wood" ("(g)wig" + "ir") or perhaps 'where two rivers meet'.