When crossing a border to enter or leave the Schengen area*, as well as when travelling from one country to another within the Schengen area (including between Switzerland and neighbouring France), you must carry a recognised and valid travel document (e.g. passport).
In addition, all nationals of countries other than the Member States of the European Economic Area** and Switzerland, unless they are specifically exempt, must carry a valid residence permit issued by a Schengen state or a valid Schengen visa.
The carte de légitimation issued by the Swiss Federal Department of Foreign Affairs (DFAE) and the titre de séjour spécial issued by the French Ministry for Europe and Foreign Affairs qualify as residence permits issued by Schengen states that allow visa-free travel to another Schengen state for a duration of up to 90 days within a 180-day period. The Host States have provided the Schengen authorities with specimens of the above-mentioned residence permits, which are included in Annex 20, Part II of the Schengen Manual, available here: https://home-affairs.ec.europa.eu/system/files/2020-09/handbook-annex_20_part2.pdf.
In the event of difficulties when presenting a carte de légitimation, the authority carrying out the check can be invited to contact the International Security Police at Geneva International Airport for information by calling +41 22 427 58 30 (until midnight) or + 41 22 427 92 20 (24 hours a day).
* https://home-affairs.ec.europa.eu/policies/schengen-borders-and-visa/schengen-area_en
** https://www.service-public.fr/particuliers/ glossaire/R42218 /; https://www.eesc.europa.eu/en/tags/european-economic-area
Relations with the Host States service
relations.secretariat@cern.ch
www.cern.ch/relations/