The Basilica of the Heart of Jesus was designed by the Croatian architect Janko Holjac in the neo-Baroque style. It is the second largest church in Zagreb. The construction of the church is tied to the arrival of Jesuits in Zagreb in 1855. For this purpose, the archbishop Juraj Haulik gave a sum of 60,000 forints in 1860. However, political and economic conditions were not favorable for Haulik's idea, and it was revived four decades later by archbishop Juraj Posilović, who donated an additional sum of 12,000 forints. In 1898, a land parcel was bought for the construction of the church in the Palmotićeva street in the Lower town of Zagreb. The basilica of Heart of Jesus was finished and consecrated in 1902, with the construction itself taking slightly over a year. In 1941, the church received the status of minor basilica.
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.