Dating in 871, Tønsberg is commonly believed to have been the oldest Norwegian town and one of the oldest recorded fortified locations in Norway. According to Snorri Sturluson, Tønsberg was founded before the Battle of Hafrsfjord under which King Harald I of Norway united Norway under his rule. Tønsberg was an important trading center and site of Haugathing, the Thing (assembly) for Vestfold and one of Norway's most important place for the proclamation of kings.In 1253, King Haakon Haakonson set up a castle, Tunsberghus, at the location of the modern Tønsberg municipality.
In 1503, after the Kalmar Union collapsed, Norwegian attempts to rebel were suppressed by Danish forces. Tunsberghus fortress was destroyed by Swedish soldiers and disloyal local peasants.
Only a few ruins of the fortress are now left. The modern-day tower (Slottsfjellet i Tønsberg) was raised in 1888 as a memorial of the historic fortress. The present tower was built during 1888 as a memorial of the historic fortress. In 1971, local authorities improved the insulation. At that time new plaques were mounted inside the tower. On the sides are the gilded signatures of two modern Kings of Norway: Haakon VII (1 August 1906) and Olav V (1 July 1958).
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.