The Valkhof is on a hill overlooking the river. It is the site of a former Charlemagne fortification and the surviving Carolingian elements are quite modest. There are two buildings with a Carolingian element. The first is an octogon chapel built in the style of Aachen in the 8th or 9th century. The initial building was constructed about 1000 and rebuilt about 1400. It used material from Charlemagne's fortification and we think we could identify some of these Caroilingian flat bricks. The second building is the ruin of Barbarossa's chapel that incorporated several Carolingian capitals on Roman pilars in the chapel.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.