This is one of comparatively few castle hills along the banks of the Daugava River that is not overgrown with trees and bushes, which means that it has a classical castle hill form that is part of the local landscape.  The Dignāja castle hill was settled during several periods, particularly between the 5th and the 9th century AD, when it was an important centre.  Archaeologists have found that Lettigalian tribes lived here.  After the Holy Crusade invasion, the Livonian Order built a castle on the hill that has not survived.  It is said that there was once an underground passageway under the hill.  The hill itself offers a lovely view of the Daugava River valley.  World War I trenches have been preserved the area.  There was once a settlement at the foot of the hill.

One of the most important military and political elements of the Livonian Order, the Bauska Castle was built between 1443 and 1456 at the place where the Mūsa and Mēmele rivers flow together.  The castle had five towers and walls that were up to three metres thick.  Between 1580 and 1596, the forecastle was replaced with a residence for the duke of Courland, and its walls were finished with the sgrafito technique.  The castle suffered damage during wars in the 16th and 17th century, but it was always restored until 1706, when the Russian military blew it up during the Great Northern War.  Today the castle houses a museum, with a viewing platform in its south-eastern tower.