Gimpo airport is now used for domestic passengers and since 2002 World Cup Korea/Japan the flight between Seoul and Tokyo has been operated. (16 flights per day nowadays). The domestic terminal of recent days was International Terminal 1 (1980s~2001) so I think the passenger terminal is spacious enough and the structure is pretty simple you wouldn't miss your way. From 2004 KORAIL (the Korean Railway Corporation) begins the KTX( the high-speed train) service so KAL and JAL devote themselves to promoting people to use their fleet but the result is "decreased domestic flight schedule". So Gimpo Airport is not so crowded during weekdays (except early-morning of Monday and Friday evening). The interior decoration is modern and illuminance is well. Above all Koreans have the thought that the toilet makes the entire image of the building so you would be surprised at the cleaness of the toilets inside the terminal. Consequently I think Gimpo Airport is good for the 2nd airport of the capital of certain nation.