The Niederburg ruins ('Lower Castle') at Kobern stand at a height of about 150 metres above the village of Kobern on a hill ridge that points towards the Moselle. On the same ridge and about 50 metres higher, is the Oberburg ('Upper Castle') and St. Matthias' Chapel.
The castle has an amygdaloidal ground plan. It has a three-storey, 20-metre-high bergfried, measuring 7.5 x 8 metres, with an elevated entrance at a height of 10 metres. There are also the remains of a two-storey, Late Gothic palas. A wall tower and a cistern are also well preserved and there are significant portions of the outer walls. The castle was guarded to the west by a curtain wall with a zwinger and to the north by a throat ditch. The upper third of the bergfried and the battlements were rebuilt in the 19th century. Between 1976 and 1978, the state castle administration reconstructed and enhanced the palas and the cistern between the two towers.
The castle was built in the mid-12th century. It is first recorded in 1195, when the then Burgherr made it a fiefdom of the Electorate of Trier. The female line of the lords of Isenburg-Kobern died out in the 13th century. The Kobern Castles and associated lordship passed via the heiress, Cecilia, to Frederick II of Neuerburg (a side line of the counts of Vianden). In 1309 the male line of this family also died out. Thereafter the castle and lordship was sold to the Archbishop of Trier. In 1688 the castle was destroyed.
The castle is open to the public all year round and may be visited free of charge. Visitors may climb up to the castle on a footpath from the Mühlbach valley.
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.