Follow signs for "Aéroport", "Lyon" and "Meyrin". Once you are in Meyrin, follow signs for "St Genis" (which is just beyond the border, in France). Before reaching St Genis, the CERN site is on your left on "Route de Meyrin", just before you reach the border.
From France (département of Ain)
Follow signs for "Gex" or "St. Genis". When you reach the border, CERN is on your right immediately after passing through customs.
Visitors can park between the entrances A and B. Please print one of the maps below and give it to your driver.