The Imperial Palace in Ingelheim was erected in the second half of the 8th century. Charlemagne chose Ingelheim in 787 as the location for his winter quarters, arriving there before Christmas and remaining there without interruption until the middle of 788. However the palace was not completed before completed before 814. It served Emperors and Kings as a residence and place for governance until the 11th century. From the buildings of the Imperial Palace impressive relics above ground are preserved today. The greater part of the complex remains as foundation under ground level and allows it to be the basis for archaeological excavations to reconstruct the entire system of buildings.
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.