The Church of St Petka of the Saddlers is a small one-naved building partially dug into the ground located in the very centre of both the modern and the antique city, in the TZUM underpass. The church features a semi-cylindrical vault, a hemispherical apse, and a crypt discovered during excavations after the Second World War. The walls are 1 m thick and made from brick and stone.
The church was first mentioned in the 16th century and was constructed at the place of a former Roman religious building. It is today a monument of culture known for its mural paintings from the 14th, 15th, 17th and 19th century depicting biblical scenes.
The church is dedicated to St Petka, an 11th-century Bulgarian saint. The Church of Saint Petka acquired its present name due to it being a patron of the saddlers in the Middle Ages, who performed their rituals in the church. The adjective samardzhiyski ('of the saddlers') was derived from the Ottoman Turkish word semerci, meaning 'saddlemaker'.
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.