Ham Wall is an English wetland National Nature Reserve (NNR) 4 kilometres (2.5 mi) west of Glastonbury on the Somerset Levels. It is managed by the Royal Society for the Protection of Birds (RSPB). Since the last Ice Age, decomposing plants in the marshes of the Brue valley in Somerset have accumulated as deep layers of peat that were commercially exploited on a large scale in the twentieth century. Consumer demand eventually declined, and in 1994 the landowners, Fisons, gave their old workings to what is now Natural England, who passed the management of the 260 hectares (640 acres) Ham Wall section to the RSPB.