 The monastery of Santa María de Óvila was founded in 1175 by a grant of land from King Alfonso VIII of Castile to the Cistercian monks of Valbuena Abbey in Valbuena de Duero , Valladolid Province , Castile @-@ Leon , Spain . In this endeavor , the king was following a general strategy of establishing Catholic institutions on land he had recently won in battle from the Moors of Iberia . The Cistercian " white monks " ( wearing undyed habits ) first chose a site in Murel ( now called Carrascosa de Tajo ) on the Tagus , but after a few years , had to relocate to more fertile zone a few miles nearer to Trillo , Guadalajara , where a flat hilltop by the river commanded a modest view . 
