Koldinghus is the town’s extravagant showpiece, with the requisite turbulent history. A fortress occupied the land in 1268, while parts of the castle you see today can be traced to the mid-15th century. After a huge fire in 1808, the prevailing school of thought was that the castle would be left in ruins (at the time, the Danish state was at war and bankrupt). Now, however, the reborn castle shines, and the interplay between old and new architectural styles is a highlight.
There are good displays, including collections of art and silverware, and changing contemporary exhibits – grab a floor plan to help find your way around. It’s a climb to the top of the tower but you’ll be rewarded with a panoramic view of the town.