The Church of St Peter and St Paul, the co-cathedral of the Roman Catholic Archdiocese of Đakovo-Osijek, is a neo-Gothic sacral structure located in Osijek. The multi-tiered 90-metre spire is one of the city's landmarks. The church was built in 1898 on the initiative of the Bishop of Đakovo Josip Juraj Strossmayer.
The church is entered via a small door to the right of the main portal, overlooked by a trio of gargoyles. The interior is a treasure trove of neo-Gothic ornamentation, with a succession of pinnacled altars overlooked by exuberant stained glass windows. The interior was finished off in 1938–1942 when leading Croatian painter Mirko Rački covered the walls and ceilings with brightly coloured frescoes illustrating famous episodes from the Old and New Testaments.
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.