Hagby Church is one of Sweden's few preserved round churches, and is considered by many to be the best preserved one in the country. The predecessor of Hagby stone church was the wooded Saint Sigfrid chapel, which was located about two kilometres south of the present church structure. The construction of this stone church began in the late 12th century. By 1541 it was abandoned.
The structure was meant to serve both as a sanctuary and a fortified building. As a result, the upper part of the walls has openings for shooting and spear throwing. The most recent renovation has attempted to emphasize the old nature of the building, so that it is now perhaps the best example of round church architecture, which otherwise is generally mostly found on the island of Bornholm. The triumph crucifix and font dates from the Middle Ages, but the interior is mainly from the 17th and 18th centuries.
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.