Reservoir of Navacerrada Nature · Navacerrada, Cuenca del Guadarrama, Madrid The Embalse de Navacerrada reservoir was built in 1969 on the río Samburiel, also called the río San Muriel or río Navacerrada, one of the main tributaries of the Manzanares, at around 1,200 metres above sea level in the north-west of the Community of Madrid. It was created to supply water to the municipalities on the Madrid side of the sierra de Guadarrama, and was one of the main reservoirs of CASRAMA, a consortium absorbed in the late 1980s into the Canal de Isabel II, which now manages it. With a curved gravity dam 517 metres long at the crest and 47 metres high, it holds eleven cubic hectometres over about 93 hectares surrounded by pine forest and mountain meadows. Swimming and water sports are not allowed, but rainbow trout fishing is, and paths with wooden boardwalks run along its shores. Photo: Pavlemadrid commons (CC BY-SA 3.0) What to see and do in Navacerrada