Dragsmark Abbey was a Premonstratensian canonry, also known as Marieskog in Norwegian. It was founded before 1260, with the support of King Håkon Håkonsson, and was dedicated to the Blessed Virgin Mary. The abbey was very wealthy in its heyday and ran a prestigious school, but declined during the 15th century, and as early as 1519 was in the control of a lay administrator, the first monastery in Norway to be secularised. With the Reformation the Crown granted it to a tenant in 1532, with a condition that the remaining canons had to be maintained. The buildings fell into disrepair, and in 1610 were used as a quarry for stone for the construction of Båhus Fortress.
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.