The church on Hjarnø is one of the smallest churches in Denmark; it currently serves 87 parishioners. The church building appears to date from the 16th century. Although it originally lacked a bell tower, one was added in 1877 with a bell dating from 1425. Within the church, the granite baptismal font is made in the Romanesque style and dates from the 12th century. The altarpiece was carved by Jens Hiernøe in 1805. Hanging from the ceiling, there is also a model Viking ship, which was donated to the church by the Glud Museum in 1955.
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.