St. Stephen's church is one of the oldest in Piran, and in the 13th and 14th centuries it was also one of the most important sacral buildings in the town.
The seat of the order of the Brotherhood of a Happy Last Hour used to be in the church, where they prayed and kept relics in the main hall and in the attic. Inside the church there are statues of the St. Stephen and St. Lawrence, as well as paintings by Jakob and Matej Palma.
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.