Anglesey the island. The highest six are Holyhead Mountain, ; Mynydd Bodafon, ; Mynydd Llaneilian, ; Mynydd y Garn, ; Bwrdd Arthur, ; and Mynydd Llwydiarth, . To the south and south-east the island is separated from the Welsh mainland by the Menai Strait, which at its narrowest point is about wide. In all other directions the island is surrounded by the Irish Sea. It is the 51st largest island in Europe, and just five square kilometres smaller than Singapore. There are several small towns scattered around the island, making it quite evenly populated. The largest are Holyhead, Llangefni, Benllech, Menai
Holy Island, Anglesey Holy Island, Anglesey Holy Island (, 'the island of (Saint) Cybi') is an island () on the western side of the larger Isle of Anglesey, Wales, from which it is separated by a narrow, winding channel. It is called "Holy" because of the high concentration of standing stones, burial chambers, and other religious sites on the small island. The alternative and historic name of the island is Holyhead Island. According to the 2011 UK Census, the population was 13,659, of which 11,431 (84%) lived in the largest town, Holyhead. Irish pirates invaded Anglesey following the end of Roman rule in