From the CERN English website:
CERN’s Visits Service organises tours of its experimental areas and facilities, which are free of charge. Tours in several languages are organised on Mondays to Saturdays starting at 9 a.m. and 2 p.m. It is essential to book in advance.
Please note that the tours are not suitable for children under 14 years of age.
(emphasis mine, as people say in history books).
Now from the French version:
Le service des visites du CERN organise des visites gratuites de sites d’expériences et d’infrastructures. Ces visites sont proposées en plusieurs langues, du lundi au samedi, à 9h ou à 14h. La réservation est obligatoire.
Veuillez noter que le niveau des visites n’est pas adapté aux enfants de moins de 10 ans.
