To the 75,000 visitors of the #CERNOpenDays: thank you for exploring the future with us and sharing our passion for science!
Remember that CERN is open all year (, so we hope to see you again soon.
For images of the OpenDays visit

CERN Open Days 2019 | 14–15 September

On 14 and 15 September 2019, CERN will open its doors to the public for two special days at the heart of one of the world’s largest particle-physics laboratories.

The CERN Open Days have become a regular feature of the period that we call the “long shutdown” during which our accelerators stop for around two years, to benefit from upgrades and renovation work. We are now in Long Shutdown 2.

The 2019 Open Days will give visitors the chance to discover our facilities, both underground and on the surface. With free admission to debates, film screenings, theatre performances, experimental workshops and dozens of visit points spread all over the site, we will take you to the heart of our Laboratory, in direct contact with the science of today and tomorrow.

The Open Days are a unique opportunity to visit CERN, don’t miss it.


Watch the CERN Director-General's talk at 10 a.m. (activity ME.24 or via
Don't have a ticket for #CERNOpenDays? You can still take a chance to come on site. ATLAS is already busy but there are plenty of activities elsewhere in Meyrin and on the other sites
Head to points 5, 6 and 8 for many activities on the surface and a chance to descend 100 metres underground
Registration at Meyrin will be busy, so consider arriving at another point even if you ticket says "Meyrin"
Welcome to day 2 of the #CERNOpenDays!