Mining settlement of Cerredo Historical milestone · Degaña, Narcea, Asturias Hullas del Coto Cortés began working the anthracite in 1919, which made Cerredo grow; in the 1940s the El Mangueiro mining railway was laid and the valley's blocks of workers' housing were built. 1919 Photo: Cerredocristobal (CC BY-SA 3.0) What to see and do in Degaña