The Arlanzón reservoir Nature · Arlanzón, Burgos (Alfoz), Burgos Image of Arlanzón, not of the place itself. A concrete, curved-plan gravity dam, built in the municipalities of Villasur de Herreros and Pineda de la Sierra to regulate the headwaters of the river Arlanzón and prevent the snowmelt of the Sierra de la Demanda from causing the floods that periodically inundated Burgos and its lower course, as recalled by the water marks preserved at the city's town hall. It was decided on after the 1930 flood, built between 1929 and 1933, and is managed by the Confederación Hidrográfica del Duero. Its capacity of 22 million cubic metres proved insufficient, so in 1983 the Úzquiza reservoir was built a few kilometres away; it now handles the river's main regulation while both dams are managed jointly to supply the Burgos area. Photo: Lucas Martínez Farra… (CC BY-SA 3.0) What to see and do in Arlanzón