Mietoinen Church was built in 1641-1643 and it’s one of the rare stone churches built after the Reformation in the 17th century. It was funded by Henrik Fleming, who was the owner of near Lehtinen manor. The church has been reconstructed several times in the 19th century, and the tower was added in 1818-1819. There are some medieval artefacts inside the church, like the wooden crucifix from the 16th century.
Mietoinen church replaced the previous wooden church known as the Hietamäki chapel. First record of the chapel dates back to year 1366, but the site has been used as cemetery from the Iron Ages.
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.