Lyckå (Lyckeby) Castle was built in 1545-1560 according the order of Kristian III of Denmark. It replaced a small castle manor and was purposed against the rebellious peasants. Battles between Denmark and Sweden were fought in Lyckå in 1507 and 1564. The castle was demolished in 1600 after Lyckå lost its city privileges to Kristianopel. Kristian IV of Denmark ordered to use castle stones to build new fortifications in Kristianopel. Today foundations of castle and two corner towers remain.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.