ICAO airport codes in Switzerland: L = Southern Europe S = Switzerland Z = Flight Information Region (FIR) Zürich with telex (back then) G = Flight Informati

ICAO airport codes in Switzerland: L = Southern Europe S = Switzerland Z = Flight Information Region (FIR) Zürich with telex (back then) G = Flight Information Region (FIR) Geneva with telex (back then) P = Flight Information Region (FIR) Zürich without telex (back then) T = Flight Information Region (FIR) Geneva without telex (back then) M = Military X = Heliport Some examples: LSZH = Zürich International Airport LSZX = Schänis Private Airfield (but with telex back then!) LSGG = Geneva International Airport LSGK = Saanen Private Airport LSME = Emmen Military Airfield LSMM = Meiringen Military Airfield LSPV = Wangen-Lachen Private Airfield LSPN = Triengen Private Airfield LSTR = Montricher Private Airfield LSXS = Schindellegi Private Heliport An interesting case is Bâle-Mulhouse, a binational French-Swiss airport located in France: It's primary ICAO code is LFSB (F = France), however, for AFTN, there's also LSZM. AFTN = Aeronautical Fixed Telecommunication Network.