some of which supply drinking water to towns and cities in the English West Midlands (Elan Valley group of reservoirs), to the towns of northern Ceredigion (Teifi Pools), and to towns all along the River Severn valley (Llyn Clywedog). Drainage It is drained by the Afon Claerwen, Afon Teifi, Afon Cothi, Afon Tywi, Afon Irfon, Elan Valley, Afon Gwy, Afon Ystwyth, Afon Mynach, Afon Rheidol See also Elenydd References Other sources External links Campaign for the Protection of Rural Wales: Historic Landscapes : Elenydd Desert of Wales, The Desert of Wales, The