In the 2nd century AD, the city-sanctuary of Gisacum extended near Saint-Aubin, which was gradually abandoned until disappearing in 5th century. In the 1801 archaeological excavations uncovered this important Gallo-Roman site; but in reality at the time the town covered an area of 250 ha. The interpretation centre has a permanent exhibition tracing the history of Gisacum, and the archaeological garden offers an original development of the thermal baths, which helps to visualise the disappeared monuments, in a pleasant landscape setting.
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.