This fortified gatehouse served as the official entry to the city ever since its construction in the 14th century, as part of the Grand Rampart which surrounded Verdun in the Middle Ages. The gatehouse was offered to the city by Wautrec, a rich citizen who was an alderman. It symbolised the new status of Verdun which was made an “imperial free city” in 1374. By this the city was obliged to maintain its own ramparts and to look to its own defence in the case of an attack.
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.