San Benito de Alcántara is a monastery in Alcántara. After the Christian conquest of Alcántara in 1213, the city was given to the military Order of Calatrava four years later. In 1218, they in turn ceded it to the order of San Julián de Pereiro, which changed its name to that of the military Order of Alcántara. In 1488, the order's council decided to build a new monastery in the city. Construction began in 1505 and lasted for most of the 16th century. The order's main architect, Pedro de Ybarra, worked on the design.
In 1706, it was sacked during the War of Spanish Succession, and it was damaged by the 1755 Lisbon earthquake. In 1835, it was abandoned and began to fall into ruin. Later it was acquired by Hidroeléctrica Española, which restored it and occupied the structure until 1966. In 1985 it went to the Fundación San Benito de Alcántara.
The exterior's main feature are the three apses (the central polygonal and the side ones semicircular), characterized by large coat of arms. Opposite a three-storey loggia with Renaissance arches, a semicircular auditorium has been built; the classical theatre festival of Alcantara is held here in the summer.
The interior has a nave and two aisles. The cloister, in Gothic-style, has a square plan with two floors. It was built atop an Moorish fortress.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.