'Gimpo' International Airport (GMP) is located in the far western end of Seoul, some 15 km (9 mi) west of the Central District of Seoul. 'Gimpo' was the main international airport for Seoul and South Korea before being replaced by Incheon International Airport in 2001.

It now functions as Seoul's secondary airport. In 2015, 23,163,778 passengers used the airport, making it the third largest airport in Korea, as it has been surpassed by 'Jeju' International Airport.

The name 'Gimpo' comes from the nearby city of 'Gimpo', of which the airport used to be a part. On 29 November 2003, scheduled services between 'Gimpo' and 'Haneda' Airport in Tokyo, Japan resumed. Services to 'Shanghai Hongqiao' International Airport resumed on 28 October 2007.

Services to 'Kansai' International Airport in Osaka, Japan started on 26 October 2008. Services to 'Beijing' Capital International Airport started on 1 July 2011. Services to 'Taipei Songshan' Airport started on 30 April 2012.

The airfield was originally constructed in 1935–1942 during the Japanese Imperial period as an Imperial Army base. In 1958, the airport was redesignated as the 'Gimpo' International Airport of Seoul by a presidential decree, completely replacing the existing 'Yeouido' Airport.

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