Bayer Factory, La Felguera Curiosity · Langreo, Nalón, Asturias At this Bayer plant, located in Lada on the other side of the Nalón river but known as the La Felguera Plant, one hundred percent of the German company's worldwide acetylsalicylic acid has been produced since 2013, as confirmed by the company itself. It was founded in 1942 as PROQUISA, to make use of gas from the Duro Felguera blast furnaces, producing crude benzol, phenol and acetic acid and anhydride; in 1952 it began manufacturing acetylsalicylic acid, with barely 90 tonnes a year, the first time the active ingredient of aspirin was made in Spain, although encapsulation was done in Barcelona. Bayer bought Proquisa in 1969 and integrated it in the 1980s. Despite the end of the steel industry in that same decade, the plant has been modernised and remains active, one of the last major factories in the council. Photo: Yandrak (CC BY-SA 4.0) What to see and do in Langreo