Ruins of the medieval town-fortress Hotalich are located 4km north-west from the today`s town of Sevlievo. The fortress was built by the Byzantines in the 5th century. In 10th century, at the same location, the Bulgarian state began construction of defense facilities to defend the country from the barbarian invasions from the north and Byzantium from the south.
The fortress was the largest in area except these of the old Bulgarian capitals Pliska, Preslav and Veliko Tarnovo.The excavations of medieval town of Hotalich and the fortress began for the first time in 1981. The archaeologists were found a high tower, two parallel walls (first of them dates back to the Early Byzantine period and the second from the 9th-10th century), remains of two main gates, ruins of quarters, churches, palace of the boyar (the local ruler), etc.
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.