Castillo de Castro Caldelas is a 14th-century fortress perched on the highest point of Castro Caldelas in Galicia's Ribeira Sacra region. Built between 1336 and 1343 by Pedro Fernández de Castro to defend his domains, the castle played a significant role in the Irmandina Revolt of 1467-1469, one of medieval Europe's greatest social uprisings. Today, it houses an ethnographic museum and local tourist office within its stone walls. Visitors can ascend the tower for panoramic views across the Río Sil valley, while the interior contains the municipal library, an auditorium, and exhibits exploring the castle's medieval heritage and local culture.