The first mention of Frías Castle, one of the most spectacular rock fortresses in Castile, dates back to the year 867, when these lands marked the border between Christian and Muslim territories. The current complex, however, is a mix of constructions from the 12th to 16th centuries, which served military purposes until the end of the War of Independence. To access it, it was necessary to cross a moat dug into the rock through a drawbridge that led to the artillery courtyard, under which a large cistern is located. The south wall displays several well-preserved windows adorned with beautiful Romanesque capitals showing carved figures of warriors and mythological animals.