town, Isle of Anglesey (Anglesey, Isle of) county, historic county of Anglesey (Sir Fon), Wales. Situated on the River Cefni almost in the middle of Anglesey island, the town originated as a market centre for the island's agricultural activity. The Moriah Calvinistic Methodist Church, one of the town's several Nonconformist churches, commemorates John Elias (1774–1841), a well-known pulpit orator of the Welsh Methodist Revival who fled to Llangefni when forced to take refuge from an angry mob in Beaumaris. Llangefni has remained a bustling market centre, and livestock are brought from all over the island for trading every Wednesday and Thursday. The town is the administrative centre of Isle of Anglesey county. Pop. (2001) 4,662.