Baltadvaris Castle was a fortified manor house, earlier sometimes classed as a bastion castle. The masonry castle with wooden fortifications was constructed by Swedish in the 16th century, in a bend of the River Siesartis, in order to secure the road from Vilnius to Riga against attacks from Livonia. It used to be the property of the princely Giedraičiai (Giedroyć) family. The neglected castle and fortifications gradually fell into ruins. Today only the foundations remain as well as parts of the walls and of the castle gates, together with several cellars.
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.