Fondón Pit Monument · Langreo, Nalón, Asturias Pozo Fondón is located beside the Nalón river, in Sama de Langreo, where the La Nalona mountain mine had already been opened in 1840. Duro Felguera deepened the shaft in 1905, making it the second vertical mining shaft opened in Asturias; in fact it is two shafts, Fondón I, 483 metres deep, and Fondón II, 378 metres deep. During the postwar period it housed a penal colony, closed at the end of 1958, and its extraction activity ceased in 1995. Buildings such as the 1915 engine house and the mid-20th-century loading pavilions, with mining mosaics by Luis Suco-Sánchez, are preserved. Today it houses Hunosa's historical archive, is the headquarters of the Central Mine Rescue Brigade and, since 2022, has had a geothermal station. Photo: Yandrak (CC BY-SA 4.0) What to see and do in Langreo