Lilleborg is a ruined castle in the Almindingen forest. The castle was probably built in the middle of the 12th century as a royal fortress. It appears to have replaced the much larger fortress of Gamleborg which was only 700 metres away. The move could be explained by the fact that in 1149, three-fourths of Bornholm had been surrendered to Eskil, archbishop of Lund. As a result, King Sweyn III wanted to establish his own seat of power on the remaining fourth of the island. While it could not be compared to the archbishop's Hammershus, Lilleborg was nevertheless a fine stronghold and appears to have been easier to defend than the much larger Gamleborg. There is evidence suggesting the fortress burnt down in 1259 when Prince Jaromar of Rügen stormed and destroyed the 'king's stronghold' on Bornholm. However, coins minted after that date have been found, indicating it was inhabited after its storming.
Lilleborg's construction inland rather than on the coast has been compared to that of Refshaleborg on Borgø in Maribo lake. It had a large tower, 9.5 metres square, protecting the entrance to the courtyard. Its walls were 2.4 metres thick and from the top it was easy to hit anyone trying to attack. The fortress is further protected by a curtain wall which follows the cliff tops around the oval plateau. The interior was some 76 metres long and 41 metres wide. When its defenses were obsolete, the fort's stones were re-purposed for other buildings. From 2006 to 2011, restoration work was carried out at Lilleborg.
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.