Piedrabuena Castle is part of defense line of Guadina and Tajo rivers near Portugal border. The oldest parts date from the late 14th and early 15th centuries. It has been head of the Encomienda of the Order of Alcántara since the 13th century.
The exterior enclosure is a quadrangular construction with cylindrical towers at the corners. In the interior there are four corridors, the keep and the prison tower. The residential function of this building is easy to see, with galleries open to the outside and a cloistered patio, all in the manner of an urban palace.
Today Piedrabuena Castle is privately owned.
The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.