Langreo
Langreo (Asturian: Llangréu) is a city and municipality in the Nalón Valley in Asturias, Spain, with a population of approximately 38,000–43,000. Historically a vital coal mining and industrial center, it is transforming into a cultural hub with significant industrial heritage, including the Ecomuseum of the Samuño Valley and the Museum of the Siderurgy.