round Tower

Round Tower was built at the initiative of Christian IV with his Steenwinckel the Younger as an architect. The tower was the first part of the Trinity complex that would bring together the three most important facilities for the 1600s scholars: astronomical observatory, student church and university. The tower itself was finally finished in 1642, the church was consecrated in 1656 and the library in the 1657th

Today used Rundetarn beyond as a tourist attraction as an observatory for exhibitions and concerts. In fact it has been used for observatory ever since 1642, and thus is the Round Tower the oldest functioning observatory. Each year there are approximately 8 exhibitions in the round tower, which comes as a surprise to most visitors.