Vyborg Old Cathedral is the oldest building in Vyborg, but today only some parts of its walls and the tower remain. The parish of Vyborg was established during the third crusade around the year 1293. There were several wooden churches the last one was destroyed by Novgorodians in 1411.
The construction of stone-made cathedral was began in 1430s and in was completed around 1445. The medieval appearance is unknown, because parts of the cathedral have been changed and demolished several times. The original nave was probably about 37m long and 20m wide. In addition to the main altar there were also few side altars. Unfortunately the interior is completely disappeared or destroyed in wars and reconstructions.
Some notable persons has been buried to the church like nobleman Erik Axelsson Tott and probably Mikael Agricola, the founder of written Finish language.
During the centuries the Vyborg cathedral was first Catholic, then Lutheran and during the Russian order also an Orthodox church. Peter the Great ordered to renovate it for Orthodox worships in 1720. In 1805 it was remodified as a magazine. In 1913 the cathedral was again restored and after the Independence of Finland it was moved once again Lutheran church. In the Winter War (1940) the aerial bomb hit the church and only walls survived.
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.