The Round Tower's newly restored Observatory reopens to visitors for Culture Night 2026, with astronomy guides on hand to help guests navigate the night sky through the historic, freshly restored telescope. Depending on weather conditions, celestial objects such as Saturn may be visible.
The theme of the evening is light, marking the 350th anniversary of Ole Rømer's discovery of the speed of light. The Spiral Ramp will be illuminated from bottom to top, guiding visitors upward through a series of engaging astronomy presentations using visual tools to explore the sun, moon, and stars.
Along the Spiral Ramp, visitors will also discover the winning images from the Round Tower's year-long photography competition, which invited entrants to capture the unique architecture of the complex and the interplay of light within it.
Halfway up, the Library Hall hosts two exhibitions on the theme of light. The first, Ole Rømer and the Great Discovery, tells the story of the scientist and former Round Tower director whose measurement of the speed of light changed astronomy forever. The second, Light Echoes, brings together artists, curators, and astrophysicists across four installations and an immersive soundscape to explore how light and time shape our understanding of cosmic phenomena.
Entry is through Rundetaarn at Købmagergade 52A, 1150 Copenhagen. Tickets are available via the Round Tower's website.