The castle of San Esteban de Gormaz is one of the key castles that changed ruler once and again during the 10th and 11th century when it finally came under Christian domain. During the reign of King García I, king of Leon, it was reinforced giving place to a repopulation of the town. From there, soldiers would control transit through the Douro River and they would guard the bridge that passed over this river. Nowadays, what is left of the castle is a large wall that is about two metres thick. The castle was built with ashlar stonework, possibly of Roman origin.
Near the access gate, there is a great opening in the ground known as Pozo Lairón, although is not certain what it was used for. The castle is narrow and elongated, and inside there are remains of water pools and underground constructions. Although it is quite deteriorated, it is of great importance due to its strategical location from which you can see the castle of Gormaz.
References: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.