Castillo de Piedrabuena, Medieval castle near San Vicente de Alcantara, Spain.

Castillo de Piedrabuena is a defensive complex of two enclosures: an outer square barbican with small cylindrical corner towers and an inner ward of four wings around a central courtyard. The keep's cistern now serves as a storeroom, and the upper floors of the keep and the galleries on its south and east sides have been converted into living quarters.

Built in the 13th century, the fortress served as an administrative center for the Order of Alcantara in the region between the Guadiana and Tagus rivers. A bastion added in 1547 demonstrates its continued strategic importance during the Renaissance.

The castle displays architectural elements from different periods, with Gothic structures from medieval times blended alongside Renaissance additions from the 16th century. These layers reveal how the fortress adapted over centuries to meet the changing needs of those who lived here.

The castle is privately owned, so visitors must ask the owner's permission before entering; there is no tourism-office arrangement. It stands about 10 km from Alburquerque, reached by the road heading north from that town toward Herreruela. The lower part of the semicylindrical Torre del Rey, an albarrana tower at the northwest angle, can still be walked through.

A notable feature is a 1547 bastion with a stone-carved heraldic shield depicting King Charles V and the Order of San Julian de Pereiro. This rare symbol shows the fortress's connection to both secular and religious powers of its era.