Malltraeth Marsh (also spelled as Malldraeth; Welsh: Cors Malltraeth or Cors Ddyga) is a large marsh area in Anglesey, North Wales, north-east of Malltraeth village, along the flatlands of Trefdraeth, Bodorgan, Llangristiolus and south of Cefn Cwmwd, Rhostrehwfa. It was reclaimed from estuarine marshes after the construction of the Malltraeth Cob (dyke), a 1 mile (1.6 km) long embankment,[1] and the subsequent canalisation in 1824 of the Afon Cefni.[2]
The name Malltraeth comes from mall ('bad'), and traeth ('sandy shore').[3] The marsh measures 1,366.5 hectares (3,377 acres) in area. The area is recognised as a Site of Special Scientific Interest (SSSI), and has a range of reedbeds, marshes, wet grassland and small pools/lakes.[4]
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