Campoo

Campoo (formally Campoo-Los Valles) is a comarca (district) of Cantabria (Spain) located in the High Ebro. With an area of slightly more than 1,000 km², it includes the municipalities of Hermandad de Campoo de Suso, Campoo de Enmedio, Campoo de Yuso, Valdeolea, Valdeprado del Río, Valderredible, Reinosa, Las Rozas de Valdearroyo, Santiurde de Reinosa, Pesquera, and San Miguel de Aguayo. The local inhabitants are called Campurrians (Campurrianos, in Spanish). Its highest elevation is the Cuchillón peak (2,225 m above sea level), and the lowest is Pesquera (560 m), with the capital, Reinosa at 850 m.

According to the Book of Merindades of Castile (from circa 1352), the merindad (subdivision) of Aguilar de Campoo comprised municipalities in the south of present-day Cantabria, as well as of northern Palencia and Burgos, with its capital at the Palentine Aguilar de Campoo (also the former capital of the vast marquisate of Aguilar de Campoo). Later the capital was moved to Reinosa, which still holds this status today. Since the province's division, Aguilar de Campoo has been part of the large comarca of Palentine Mountain.