Vårfruberga Abbey, previously Fogdö Abbey was a Cistercian nunnery from the 12th century until 1527. In the 12th century a house of Benedictine nuns was established in Fogdö, but its exact location is obscure. Excavations in 1991–92 revealed that a medieval fortification had been built on an elevation near the water, and it is possible that the nuns were displaced from their original place of settlement on this strategic site to make room for the fort. This would explain why they moved to what is now Fogdö church, where the nunnery was located from 1233. The church was used both as a parish church and as a monastic one, as is testified by an inset opening in the south wall - a so-called 'nun's window' ('nunneporten'). The quire was also widened so as better to accommodate the nuns' choral liturgy. Judging from the surviving walls, the services of a builder trained in the Cistercian style were obtained for the project. In 1252 the abbey was sent a letter offering protection from, and sealed by, Birger Jarl and his son Valdemar, which is still preserved in the Riksarkivet.
After 50 years the nuns moved again to the present Kungsberg (3 km east of Fogdö), where they were able to have built a full monastic complex in accordance with the Cistercian principles of monastery construction and layout. The new buildings were put into operation in 1289. At the same time the name of the community was changed to Vårfruberga ('Mountain of Our Lady'), and was formally accepted into the Cistercian order, as a daughter house of Julita Abbey. The church was built in the shape of a Latin cross, with three aisles and a short transept. The nave was divided by a wall to separate the nuns from the lay congregation. The church was roofed with tiles, and the external walls may also have been tile-clad.
In the Reformation Gustav Vasa dissolved the abbey in 1527 and appropriated its property and estates to the crown. He had the monastery buildings demolished to use as a source of stone for the construction of Gripsholm Castle. Parts of the walls survive.
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.