Lake Vyrnwy

Lake Vyrnwy is a reservoir in Powys, Wales, built in the 1880s for Liverpool Corporation Waterworks to supply Liverpool with fresh water. It was the first large stone-built dam in the United Kingdom and cost £620,000 (equivalent to £90 million in 2023) When the reservoir is full, it is 26 metres (84 ft) deep, contains 59.7 gigalitres (13.125×10^9 imp gal), and covers an area of 4.54 square kilometres (1,121 acres) The lake has a perimeter of 19 kilometres (12 mi) with a road that goes all the way around it. Its length is 7.64 kilometres (4.75 mi) The reserve is designated as a national nature reserve, a Site of Special Scientific Interest, a Special Protection Area, and a Special Area of Conservation. The lake is a popular destination for ornithologists, cyclists and hikers. It is listed as a Grade I historic building by Cadw as a historic building of historic interest. The dam was designed to prevent a build up of pressure beneath the base of the base.