The interior spiral ramp consists of seven and a half turns around the hollow core of the tower.
Tsar Peter the Great of Russia famously drove a horse and carriage up the spiral ramp during his visit in 1716.
The tower's hollow core is measured as the zero point for all national geodetic measurements in Denmark.
The observatory at the top is still actively used for star-gazing sessions during winter months.
The tower was built without stairs to allow a horse-drawn cart to transport heavy, sensitive astronomical instruments to the top without damaging them.
The Latin inscription on the facade, designed by King Christian IV, translates to a prayer for God to guide the king's heart.
The Round Tower, or Rundetaarn, is a 17th-century fortification, observatory, and church complex commissioned by King Christian IV. It is Europe's oldest functioning observatory, still used by amateur astronomers. The tower is renowned for its 209-meter-long equestrian spiral ramp instead of traditional stairs, designed to allow horses and carriages to reach the library level. The structure houses the Trinitatis Church, which physically connects to the tower. Visitors can access a platform at the top that provides a 360-degree view of Copenhagen's historic center. The complex includes the Library Hall, which hosts regular art exhibitions and cultural events. The tower was constructed between 1637 and 1642 to provide a stable base for the University of Copenhagen's astronomical observations. It remains a central architectural landmark in the Latin Quarter.
The view from the outdoor gallery looking over the orange rooftops of Copenhagen's historic city center.
Walk up the ramp slowly to observe the unique interior geometry and the hollow core.
Check the exhibition schedule for the Library Hall before visiting, as it hosts rotating contemporary art installations.
Use the telescope on the observation deck if visiting on a clear, dark evening.
Avoid visiting during heavy rain, as the outdoor observation deck becomes slippery and visibility is severely limited.
Maintain a quiet volume as the tower is part of a church complex; walking on the ramp is the only way to ascend.
