The medieval church of Saint Peter and Paul in Kaarma is one of the most interesting sights in Saaremaa island. The building was probably started right after the uprising of Saaremaa inhabitants in 1261. It was a typical church of the Osilia Bishophric - a simple nave with a slightly narrower choir. The steeple was added in the 15th century and thus Kaarma became the first church with a steeple on Saaremaa.
The church is built on unstable ground and during construction an accident seems to have occurred, and part of it seem to have collapsed. The nave did not acquire its present vaults until the 15th century. The relatively wide nave was divided into two aisles for safety purposes. Sometime prior to the 15th century reconstructions, a room with a fireplace was built above the vestry. This room could serve as a place of refuge for the colonizers from the angry natives of Saaremaa. Later, it became shelter for pilgrims who followed a route that included churches on the island of Gotland and Saaremaa.
The murals on the northern wall of the choir originate from the old church. They depict a painted illusionary window and a scene with St. Christopher. Unfortunately, only the legs seem to have survived. The proceedings were observed by a hermit carrying a lantern.
Many pieces of art have survived in Kaarma church. There is a medieval baptismal font (13th century) and a wooden sculpture of St. Simon of Cyrene (mid-15th century) standing under the pulpit. The pulpit, dating from 1645, is also worth noting. The present Neo-Gothic altarpiece depicts a painting by O. von Moeller of Christ on the Cross. The niches in the altar was formerly filled by medeival carvings of the apostles. These sculptures can now be seen in the Saaremaa Museum in Kuressaare.
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.