Mikkeli Cathedral was built in 1896-1897. The large red-brick church is designed by Finnish church architect Josef Stenbäck. It represents the Gothic Revival style like many other churches designed by Stenbäck. The bell tower is in the western gable of the church. The church has 1,200 seats. The organ was built in 1956 by Kangasala Organ Factory and has 51 stops. The altar painting "Crucified" was made by Pekka Halonen in 1899.
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.