Castle of Aguilar de Campoo Monument · Aguilar de Campoo, Montaña Palentina, Palencia A rock fortress that crowns the hill above the town and controlled the crossing of the Pisuerga; it was declared a Monumento Histórico-Artístico (Spain's heritage designation in force between 1931 and 1985) in 1949 and of its walled enclosure there remain curtain walls and towers visible from across the floodplain. Photo: Goldorak (CC BY-SA 4.0) What to see and do in Aguilar de Campoo