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
Anglesey near the north coast. There are plans for the world's first Tidal Flow turbines, near The Skerries, off the north coast, and for a major biomass plant on Holy Island (Ynys Gybi). Developing such low-carbon energy assets to their full potential forms part of the Anglesey Energy Island project. When the aluminium smelting operation closed in September 2009, it reduced its workforce from 450 to 80; this has been a major blow to the island's economy, especially to Holyhead. The Royal Air Force station RAF Valley (Y Fali) is home to the RAF Fast Jet Training School and also 22