Castile and León is an autonomous community in northwestern Spain. Castile and León is the largest autonomous community in Spain by area, covering 94,222 km. It is, however, sparsely populated, with a population density below 30/km. While a capital has not been explicitly declared, the seats of the executive and legislative powers are set in Valladolid by law, and for all purposes that city (also the most populated municipality) serves as the de facto regional capital.
Castile and León is a landlocked region, bordered by Portugal as well as by the Spanish autonomous communities of Galicia, Asturias, Cantabria, the Basque Country, La Rioja, Aragon, Castilla–La Mancha, the Community of Madrid and Extremadura. Chiefly comprising the northern half of the Inner Plateau, it is surrounded by mountain barriers (the Cantabrian Mountains to the North, the Sistema Central to the South and the Sistema Ibérico to the East) and most of the territory is drained by the Douro River (Spanish: Duero), flowing west toward the Atlantic Ocean.