This airport has a large domestic terminal and a much smaller international terminal. The domestic terminal handles all Seoul’s domestic flights except for a handful of flights to and from Busan and Jejudo, which arrive and depart from Incheon International Airport.
The 1st floor is for arrivals, the 2nd floor is for checking in, and the 3rd floor is for departures. Flights, none lasting more than an hour, go to Jejudo, Busan and seven other cities. The usual shops and restaurants are inside the terminal. The international terminal only handles flights to Haneda (Tokyo, eight daily) and Shanghai (four daily). Taking this route avoids the hassle of getting out to Incheon and Narita airports, which are some distance from their respective capital cities.