Universiteit Leiden

Explore the fascinating world of science at the Open Day in the Gorlaeus Building of Leiden University. Join the tour The Search for a Medicine, go behind the scenes at NeCEN and the Fine Mechanical and Electronic Services, and discover how researchers are working on the medicines and technology of the future.

For visitors of all ages, there are also spectacular liquid nitrogen demonstrations where you can see how ice cream is made and watch a magnet actually levitate.

About Leiden University

Leiden University was founded in 1575. With seven faculties and locations in both Leiden and The Hague, the university has been contributing to science for more than four centuries. Two of those faculties are located directly on Leiden Bio Science Park: the Faculty of Science and the Leiden University Medical Centre (LUMC).


Right in the heart of Leiden Bio Science Park stands the Gorlaeus: a modern building where people work every day on the science of tomorrow. The building opened in 2024 and has been welcoming everyone curious about how science works ever since. Feel free to come and take a look!

Tour: The Search for a Medicine


What actually happens to a medicine after you take it? What route does it travel through your body, and which organs does it pass along the way? And how do researchers know where a medicine ends up and how it works?

On this tour, we take you on the fascinating journey of a medicine through the human body. You’ll discover how medicines are absorbed into the bloodstream, what substances they encounter along the way, and how they eventually leave the body.

We’ll also show you how researchers use blood measurements to trace where a medicine has been and how it spreads through the body. This is an unique chance to look behind the scenes of research that contributes to the development of safe and effective medicines.


All ages welcome!

Times: 11:00, 12:00, 13:00 (45–60 minutes)

Places are limited. Registration required in advance.

Tour: Fine Mechanical and Electronic Services


Go behind the scenes at the Fine Mechanical and Electronic Services of Leiden University, where custom-made components and smart equipment are built specifically for scientific research.

During the tour, you’ll discover how engineering and science go hand in hand, and get an up-close look at impressive machines and remarkable instruments. You’ll also have the rare opportunity to see staff at work in a space that is normally off-limits to visitors.


All ages are welcome!

This is an ongoing activity, no registration required

Tour: NeCEN


NeCEN is a unique research facility where scientists use extremely powerful microscopes to study things invisible to the naked eye. For example: viruses, proteins, and tiny components of cells. By examining these up close, they can uncover how our bodies work and how diseases develop. During the tour, you’ll see how this kind of science helps in the development of new medicines and treatments.


All ages welcome!

Times: 10.30, 11.30, 12.30 (30 minuten)

No registration required

Nitrogen Stunts


Want to watch a magnet float in mid-air and see ice cream made from nitrogen?

The students of Stichting RINO show just how fun and surprising science can be with a series of spectacular experiments. Using liquid nitrogen at a staggering -196°C, they freeze all kinds of objects and demonstrate extraordinary physical phenomena including superconductivity, which makes a magnet levitate. Through these demonstrations, you’ll discover in a playful way how the laws of nature work and why science is so much more than just formulas.


All ages are welcome!

This is an ongoing activity, no registration required