Experience the secrets of the Trinitatis Complex
On this November evening, the Trinitatis complex celebrates the light by opening its doors to hidden spaces that are normally not part of the visitor experience. Come behind the scenes at the Round Tower and Trinitatis Church, where you can explore the old apartment and the church crypts, learn more about Ole Rømer, hear music from the church organs, and catch a glimpse of the night sky from the Observatory.
As part of LIGHT YEAR 2026, a jubilee year marking the 350th anniversary of Ole Rømer’s discovery of the speed of light, the Trinitatis complex are opening up areas of the church and tower that are normally closed to visitors on this winter evening, inviting all visitors to enjoy a range of exciting experiences.
Secret rooms, stargazing and the Jovilabium
At the Round Tower, special access will be granted to secret rooms that are otherwise closed to the public. These include the Bell Loft, one of two loft spaces belonging to Trinitatis Church. Sounds strange? Come and see for yourself. The secret tour will also take you to the old apartment, offering a glimpse into life in the tower during Ole Rømer’s time as well as today.
In the Library Hall at the Round Tower, visitors can enjoy an exhibition about the astronomer Ole Rømer, who was, among other things, director of the Observatory and chief librarian of the library at the Trinitatis complex. Visitors will also have the opportunity to see a reconstruction of Ole Rømer’s remarkable Jovilabium – a fascinating mechanical and astronomical instrument that demonstrates the orbital movements of Jupiter’s innermost moons.
At the top of the Round Tower, in the newly restored Observatory, visitors can learn more about the universe – both by exploring how the nearly 100-year-old telescope is used today and how the tower was used for astronomical observations in the 17th century.
Weather permitting, it will also be possible to look through the telescope yourself and experience fascinating celestial objects – in November Saturn and its spectacular rings can often be seen in the evening sky.
Crypts and organ music
At Trinitatis Church, visitors will have access to the two crypts, where Field Marshal Hans Schack and other prominent figures from the 17th century are buried in elaborately decorated coffins. You can learn about Trinitatis Church as it looked when it was inaugurated in 1656, as well as about Hans Schack, who organised the defence of Copenhagen during the Swedish siege.
Visitors will also have the opportunity to get close to the church’s organs and learn more about both the Italian Baroque organ and the main organ through stories and live music.
All this can be experienced
At Trinitatis Church
- Access to the crypts
- Access to Hans Schack’s monument and the sacristy
- Alternating organ demonstrations and performances
At the Round Tower
- Access to the Library Hall and the two exhibitions: Ole Rømer and the Great Discovery and Light Echoes
- Demonstrations of Ole Rømer’s planetary machines at several special locations in the tower
- Access to the Observatory, with the opportunity to look through the telescope (weather permitting), as well as guidance from the observatory staff
- Astronomy presentations and a demonstration of Ole Rømer’s Jovilabium
Practical information
It is possible to register in advance via the link on the right, but you can also simply turn up at the Round Tower ticket office. The evening costs the regular admission price (DKK 60 for adults / DKK 40 for students / free admission for children). The church can be accessed through a glass door connecting the church and the tower, an area that is normally closed to visitors.
Science & Wine: Conversations on Light, Time and the Universe
Round off the week with a drink while learning something new. Meet the curator and artists behind the current exhibition “Light Echoes” as they join scientists in exploring how light shapes our understanding of time as a dimension. Afterwards, head to the top of the Round Tower and enjoy the low evening sun over the city.
The exhibition “Light Echoes”, which explores complex astrophysical phenomena through four art installations, opens on Friday 2 October in the Round Tower’s beautiful Library Hall. That same afternoon, we have invited the artists and researchers behind the exhibition to discuss one of its central ideas: how the relationship between light and time shapes our understanding of cosmic phenomena.
We use light and time not only to understand the Universe; they are also tools for observing and investigating the world around us. This is precisely why light and time can create connections between art and science. In astrophysics, light allows us to observe events across vast distances and look far back into the past. In art, light can become material, experience and trace – and a way of exploring how we perceive and experience the world. In different ways, both art and science use light to connect what we can see with what lies beyond our direct reach.
Where Art Meets Science
This Friday afternoon, round off the working week in the best possible way – with a glass of sparkling wine (or something else) in hand while listening to a panel explore how different artistic and scientific approaches to light and time can open up new perspectives and ways of thinking across disciplines.
The exhibition is curated by Irene Campolmi, curator and co-founder of Yonder | Art•Science | Niels Bohr Institute, and presents works by Jo Verwohlt and Pieter Maria Steyaert, Lea Porsager, Ligia Bouton and artist duo Semiconductor. All the artists took part in Yonder | Art•Science’s residency programme in 2025–2026. Yonder | Art•Science is a platform for collaboration between art and science at the Niels Bohr Institute.
Programme
4.30 pm
Welcome drink
4.45 pm
Introduction by Ditte Marie Lund, Head of Programme and Exhibitions at the Round Tower, and exhibition curator Irene Campolmi
5–6 pm
Panel discussion with artists and researchers from DARK at the Niels Bohr Institute who contributed to the exhibition, moderated by Irene Campolmi:
- Artist Lea Porsager in conversation with Jens Hjorth, Professor of Astrophysics and Co-founder of Yonder | Art•Science | Niels Bohr Institute
- Artist duo Semiconductor in conversation with Steen Harle Hansen, Professor of Astrophysics at the Niels Bohr Institute, and William Baker, Postdoctoral Researcher in Astrophysics
- Artists and scientists Jo Verwohlt and Pieter Maria Steyaert
- Artist Ligia Bouton in conversation with Judit Prat and Clara Ferreira Cores, interdisciplinary researchers and astrophysicists from Yonder | Art•Science | Niels Bohr Institute
Semiconductor will also present excerpts from their installation “Light in Flight”.
Please note: The panel discussion will be in English.
6–6.30 pm
Drinks and conversation, with the opportunity to visit the top of the tower
Good to know
Before and after the programme, guests can explore the Round Tower’s year-long exhibition on Ole Rømer, which introduces LIGHT YEAR 2026 – marking the 350th anniversary of Rømer’s discovery that light has a finite speed – as well as the newly opened special exhibition “Light Echoes”.
Guests can also make their way to the top of the tower and enjoy the 360-degree views of Copenhagen from the viewing platform.
The Round Tower offers a complimentary glass of wine on arrival. Additional drinks will be available to purchase during the event.
Award Ceremony for the Photo Competition
The best photographs have been selected. For the finale of this year’s photography competition, the Round Tower invites you to a jury discussion, award ceremony and first presentation of the exhibition featuring the selected photographs along the Spiral Ramp.
After eight months of competition, Capture the Light at the Round Tower (Fang lyset i Rundetaarn) culminates on Architecture Day with a festive finale at the Round Tower.
Throughout the year, photographers of all levels have explored the interplay between light and architecture at the Round Tower and Trinitatis Church. Now, the competition’s strongest entries will be revealed as the professional jury selects the 1st, 2nd and 3rd prize winners. At the same time, visitors can experience the nominated photographs displayed along the Spiral Ramp and see how light has shaped the participants’ perspectives on this historic building.
As part of the event, the competition jury will take part in a conversation about photography, light and architecture. During the approximately 30-minute discussion (NB! in Danish), the jury members will share their perspectives on what makes a strong photograph, how light can transform our experience of architecture, and the considerations behind their assessment of the submitted images.
The winners of this year’s competition will then be announced, and the 1st, 2nd and 3rd prizes will be presented.
The jury consists of:
- Klaus Nygaard, Editor-in-Chief of Digital FOTO
- Camilla van Deurs, former City Architect and partner at Nordic Office of Architecture
- Kim Høltermand, architectural photographer
The ticket price is the regular admission fee and includes a glass of wine to enjoy during the event.
Join us in celebrating photography, architecture and light – and discover which images have best captured the unique atmosphere of the Trinitatis Complex as part of Light Year 2026 and the celebration of the 350th anniversary of Ole Rømer’s discovery of the speed of light.
Before and after the event, you can experience the current exhibition, Light Echoes, as well as climb to the top of the tower and enjoy the view. On this evening, the Observatory will also be open to visitors for the first time since its extensive restoration. It will be open from 6–9 pm.
Please note: The selected photographs will be exhibited along the Spiral Ramp from 5–9 October 2026 and can be experienced until Culture Night.
The event is part of the Round Tower’s LIGHT YEAR 2026 programme, marking the 350th anniversary of Ole Rømer’s discovery of the speed of light.
Astro Bar and strings on the top of the Round Tower
Enjoy a sunset over Copenhagen with a drink in hand and classical pop covers in your ears as the Round Tower invites you to a very special Astro Bar event on the observation platform.
At the Round Tower, we are proud to claim that we offer the best view in the city and on 10 September, it will be even better as we host an evening bar event after regular closing hours. The historic kiosk at the top of the tower will be transformed into the platform’s very own bar, where guests can enjoy a drink while listening to major pop hits reimagined in classical arrangements, much like those featured in the hit TV series Bridgerton.
On the observation platform, visitors can experience the string duo String Duo Diapason, who will accompany the sunset with their classical interpretations of well-known pop songs. The duo consists of Marta Kocon on violin and Javier Palacios Semanat on viola. They have previously performed at Candlelight concerts at the Odd Fellow Mansion, the National Museum of Denmark, and during Copenhagen Fashion Week.
The Observatory will also be open this evening, and the tower’s astronomers will be on hand to share insights into celestial bodies and fascinating stories from the world of astronomy. As the Round Tower Observatory is not yet fully operational, the evening’s astronomy presentations will take place without the use of a telescope.
In the Library Hall, halfway up (or down) the Round Tower, guests can explore the current exhibition Refractions of Ice, which examines ice crystals from the Greenland Ice Sheet under polarized light. The hall also hosts an introductory exhibition to this year’s theme on light, Ole Rømer, and his groundbreaking discovery.
No advance registration is required for the event, so bring a friend, partner, parent, or colleague and join us at the Round Tower for an extraordinary evening. Please note that queues and waiting times may occur during the evening if maximum capacity is reached.
Please note:
- Bringing your own food and drinks into the Round Tower is not permitted.
- Smoking is not allowed on the observation platform.
- If weather conditions do not permit an outdoor event, the programme will be moved indoors.
Are you between 18 and 27 years old? By presenting a valid K7 card, you can enjoy free admission to the evening’s Star Bar event.
Special opening for photographers: Capture the sunset in peace
Shoot photos for The Round Towers photography competition without being disturbed by other visitors during this special late opening for photographers. If the sky is clear, you can also capture the beautiful sunset from the top of the tower.
The Round Towers photography competition, which encourages photographers to capture the light within the unique architecture of the Trinitatis Complex, has been underway since February and will conclude on October 5 with an award ceremony.
On this August evening, the tower will remain open late for photographers who would like to capture the sunset and the changing evening light within the historic architecture.
The tower normally closes at 8:00 PM, but on this evening, photographers with a free reserved ticket may stay until 10:00 PM. This gives you the opportunity to explore the tower at your own pace and experience the beautiful evening light throughout the historic building.
We encourage participants to familiarize themselves with the competition rules in advance. The rules can be found here.
Participation in this special evening opening is free of charge, but advance ticket reservation is required. Please note that the number of places is limited.
Please note: In the event of cloudy skies or poor weather conditions, the event will still take place, so you may need to think creatively.
If you have any questions, please contact us at post@rundetaarn.dk.
Special opening: A morning for photographers
Come and capture beautiful photos for the Round Tower’s photography competition without being disturbed by other visitors, as we open especially for photographers on this June morning.
The Round Tower’s photography competition, where photographers are encouraged to capture the light within the unique architecture of the Trinitatis complex, is well underway, and the first winners of “Photo of the Month” have already been announced.
We look forward to seeing even more exciting perspectives and inspiring images of the light in the Roundtower and Trinitatis Church, and therefore we invite photographers to a special morning opening on Sunday, June 14, from 8:30-10:00 AM.
Rundetaarn will not open to regular visitors until 10:00 AM, meaning photographers will have the morning to themselves (apart from other photographers and a few staff members). This offers the opportunity to explore at your own pace, including the beautiful spiral ramp, the old Library Hall and the viewing platform.
At the same time, there will be open access between the Round Tower and Trinitatis Church, where the beautiful architecture and the light also create opportunities for truly unique motifs.
We encourage participants to familiarize themselves in advance with the rules of the photography competition, which can be found here.
Participation in this special morning opening for photographers is free of charge, but ticket reservation is required (limited number of places available).
Please note: In the event of cloudy or poor weather conditions, the event will still take place (so it may be necessary to think creatively).
The historic Spiral Ramp is a favorite subject among photographers at the Round Tower.
Questions can be sent to post@rundetaarn.dk.
CPH:DOX at The Round Tower: “The Peace Particle” + Live Event on CERN
Join the documentary film festival CPH:DOX this March as it presents films from its science programme in the Library Hall at The Round Tower. On 22 March, you can experience The Peace Particle by Alex Kiehl, followed by a panel discussion on science for peace featuring, among others, Jeffrey Hangst, researcher at Aalborg University and CERN, and artist Lea Porsager.
CPH:DOX is Copenhagen’s international documentary film festival, presenting some of the strongest documentary films from Denmark and abroad each year at various venues across the city. As part of LYSÅR 2026, you can experience films from its science section in the historic Library Hall at The Round Tower, temporarily transformed into a festival cinema. Over the years, the Library Hall has housed everything from the book collection of the University of Copenhagen and storage for the Zoological Museum to a range of exhibitions on science and history.
FILM: The Peace Particle
After the atomic bomb was dropped on Hiroshima, many scientists vowed never again to use their knowledge for warfare. These researchers went on to found CERN and built the world’s largest machine in pursuit of the universe’s smallest particles. With rare access to the groundbreaking Large Hadron Collider and Nobel Prize-winning scientists, The Peace Particle pays tribute to CERN as it faces its greatest challenge since its founding in 1954: today’s threat of yet another world war.
The film runs for 86 minutes and will be followed by a talk.
LIVE EVENT: Science for Peace – A Conversation about CERN at The Round Tower
At a time when peace and international cooperation can seem elusive, the scientists at CERN remind us of one essential truth: collaboration is still possible. Join CPH:DOX and The Round Tower for a conversation about research and peace, and how the search for the universe’s smallest particles can remind us of our shared humanity.
Meet researcher and The Peace Particle contributor Jeffrey Hangst (AAU), founder of the ALPHA collaboration at CERN, in conversation with artist Lea Porsager, who has participated in the Arts at CERN project. The conversation is moderated by Anders Høeg Lammers, science editor for researchers at videnskab.dk.
Look forward to a unique experience where film about science is enriched by the historic atmosphere of the Tower. Your film ticket naturally includes access to the rest of the Tower, allowing you to explore current exhibitions in the Library Hall, the iconic Spiral Ramp, the Hollow Core, the Bell Loft, and enjoy panoramic views of the city’s spires, towers, and rooftops from the top.
The screenings are part of the LYSÅR 2026 programme at The Round Tower – a year-long celebration of light and the 350th anniversary of Ole Rømer’s groundbreaking discovery of the speed of light.
Finissage: Crystalline Memories of Deep Time
Artist Claus Spangsberg creates fascinating images at the intersection of art and science. Meet him in the exhibition on its very last day.
Claus Spangsberg specializes in microscopy and crystallization, creating images using chemical substances, DNA, and amino acids. In the exhibition Crystalline Memories of Deep Time, he explores some of the oldest materials known to us and presents various meteorites and components from the biochemical processes of the primordial soup. Materials such as crystallized sulfur, amino acids, and enzymes are presented as large-scale microscopic images or displayed in specially constructed screens with polarizing filters, allowing beautiful colors and patterns to emerge from the materials’ structures.
Meet Claus on the final day of the exhibition, when you will have the opportunity to ask questions about the works, be guided through the exhibition, and hear more about his artistic process.
The exhibition is supported by
Grosserer L.F. Foghts Fond
Den Hielmstierne-Rosencroneske Stiftelse
Knud Højgaards Fond
Poul Johansen Fonden
Lizzi og Mogens Staal Fonden
OVODAN BIOTECH
Københavns Kommune – Rådet for Visuel Kunst
Winter Light Bar
Experience the top of the Round Tower like never before, as the platform transforms into a glowing winter bar!
The view from Rundeaarn’s platform at nearly 35 metres above the ground is something truly special – even in winter.
We’re braving the cold and turning up the atmosphere when the platform is transformed into a glowing winter bar on 28 February. The music will be provided by Future Female Sounds, and with Maria Kabar behind the DJ booth, the audience is guaranteed a festive evening.
In February, the Round Tower turns up the light, as the platform becomes a radiant winter bar. There will be music and a bar that will offer beer and bubbles, as well as drinks such as “Light and Stormy” or “Glow & Tonic.” Enjoy your drink while exploring Yoke’s light installation “While the Light Hesitates” at the top, inspired by Ole Rømer’s discovery of the delay of light.
We recommend that guests bring extra warm clothing and dance to keep warm, but if that isn’t quite enough, blankets will be available to borrow.
The Library Hall will also be open. Here, you can experience the newly opened exhibition Ad Lucem, as well as the Round Tower’s historical exhibition about Ole Rømer and his discovery of the hesitation of light.
Access to the winter bar is included in the regular admission, but be aware that if interest is very high, queues may form, as the Viewing Platform allows a limited number of visitors at a time.
The event is part of the program for LIGHTYEAR 2026 at the Round Tower — a full year in which we celebrate light and the 350th anniversary of Ole Rømer’s groundbreaking discovery of the speed of light.
Concert: Ars Nova – To Love
Join the Ars Nova concert in the Round Tower and experience the internationally acclaimed vocal ensemble celebrate love in all its forms through a rich and expressive vocal repertoire, ranging from intimate closeness to universal longing.
Several of the pieces draw inspiration from the Song of Songs, but the program also features texts by James Joyce and Shakespeare, as well as tones from the Renaissance and contemporary compositions – all lovingly interpreted by the skilled vocal ensemble.
The concert brings together music that, through the centuries, has been created in the name of love. A beautiful journey through love’s many facets, to be enjoyed either alone or with someone dear to you.
Ars Nova Copenhagen was founded in 1979 and has long since established itself as one of the world’s finest vocal ensembles. The group specializes in interpreting Renaissance polyphonic choral music and new vocal works, performed with precision and emotion, and with a sound that draws attention around the globe.
The concert will take place in the historic Library Hall, where you can also view the current exhibition The Shadow Archive. Drinks will be available for purchase, and you’re welcome to end the evening with a trip to the top of the tower to enjoy the nighttime view over Copenhagen.
This event is part of the Golden Days Festival (September 5–21). The theme is ‘Love’, which you will also be able to feel at the Round Tower. Follow September’s love events right here.