With the northern half of the Spanish Meseta all its own, this is unmistakably big sky territory. It is the largest autonomous region in Spain, covering a full one-fifth of the country's territory, and is larger than some EU countries, including neighboring Portugal. The Spaniards born in this sweeping mosaic of tableland hemmed by mountains are credited with speaking the purest Castellano tongue. They gravitate toward the major cities of the region, Burgos,Valladolid, León and Salamanca, leaving vast tracts of land empty of all but shepherds and barley growers. They pray in two of the country's three greatest Gothic cathedrals in León and Burgos, study at one of the world's oldest and most influential universities in Salamanca, cast for five-pound trout in the Río Duero and excavate the remains of Europe's oldest inhabitants in the Sierra de Atapuerca.  The stereotypes of Castilla y León paint but a small picture of this vast realm. Pilgrims have trudged along the main route of the Camino de Santiago since the ninth century, a period when Christian Spain was in the midst of consolidating its forces to drive the Moors from the peninsula. Burgos would serve as the capital of the crown during the early Reconquest and eventually would be joined with the separate kingdom of León in furthering the cause.