Сьерра-де-ла-Деманда
The Vía verde de la Sierra de la Demanda is a greenway that extends over most of the path of a short-lived mining railway of the early 20th century, which carried minerals from the mines of Monterrubio de la Demanda and Barbadillo de Herreros to Villafría, in the outskirts of Burgos, Spain.