Originally Posted by
Sheikh Yerbooty
ICN is Incheon, not Seoul. SEL is in Seoul, but is only used for domestic flights these days. It's about a 1 hour train ride from Incheon to downtown Seoul.
Not so. SEL is the city code for Seoul, much as TYO, LON or NYC. The IATA code for Seoul-Gimpo, the older airport now used for domestic and short haul international, is GMP.