Anglesea, Or Anglesey, a small island in the Irish sea, on the coast of Wales, from which it is separated by the Menai strait, constituting a county; area, 302 sq. m.; pop. in 1871, 50,919. The chief agricultural products are oats and barley. Cattle and sheep are largely raised. The copper mines at Parys and Mona, once very productive, have much' declined. The chief towns are Beaumaris, the county seat, Holyhead, Llangefni, and Amlwch, which unite in returning one member to parliament, besides the county member. The Menai strait is crossed by a fine suspension bridge, one of the earliest and most perfect specimens of this style of structure, also by the Britannia tubular bridge of the Chelsea and Holyhead railway, one of the great triumphs of modern science and enterprise. (See Bridge.) Anglesea was known to the Romans as Mona, and was the last stronghold of the Druids, of whose religion various cromlechs and other remains are still extant. On the N. W. end of the island is the smaller island of Holyhead.