The Grotte di Catullo was a large Roman villa on the end of the Sirmione peninsula. The villa, built around 150 AD, is the most important example of a high-class residence in the whole of northern Italy. Just after the entrance to the archaeological park one find the Museum, where objects brought to light during the excavation of the villa, and in archaeological work conducted in Sirmione and other localities of lake Garda, are displayed.
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.