Installation of Two Tower Cranes for Building 777

Over the coming weeks, the construction site for Building 777 will take an important step forward with the installation of two tower cranes. These cranes — one 30 m high and the other 40 m — are essential for the next phases of the project and will remain in place throughout the main construction works until the beginning of 2027.

To ensure everyone’s safety during these operations, several temporary road closures and access restrictions will be required:

Crane G2 installation
18–19 December 2025
– Temporary closure of Route Touscheck for both days.
– Part of the 865 car park will also be closed on 19 December. No vehicles or pedestrians will be allowed in the marked safety zone during the lifting operations.
– Access to buildings 864 and 865 will remain possible via dedicated signage.
– All areas will reopen on the evening of 19 December.

Crane G1 installation
5–6 January 2026
– Partial closure of Route Adams during both days. Cars will have an alternative route; see yellow line
– The small parking area next to building 866 will be closed.
– Pedestrian routes will be adapted and clearly indicated.
– Traffic officers will be present on site to guide users and ensure safe circulation.

Important note – weather dependence

The installation of tower cranes is a complex operation that depends heavily on weather conditions. Dates may shift at short notice if conditions are not safe for lifting activities. We will keep the you updated should changes occur.

A safer and more welcoming CERN campus

These short-term constraints are necessary steps toward delivering a modern, efficient and user-friendly B777 facility at the heart of the CERN campus. We thank all Prévessin users for their patience and understanding as we work together to build an improved environment for CERN.

Find more information on the project here: https://building777.web.cern.ch/
Or contact the B777 team on: project-B777@cern.ch