Seoul is a very well organized city covering over 600 km² with a population of around 11.8 million. It is a new modern city built on an ancient and shining history. The city is located in the north-western portion of South Korea approximately 40 km east of the Yellow Sea and 60 km south of the Korean Demilitarized Zone (DMZ). The city is roughly bisected by the Han River (한강 Hangang), which runs east to west across the city. Seoul blurs seamlessly into its surrounding satellite cities, most of which are also served by the Seoul metro. The largest of these is Incheon (to the west) in which Seoul's main Airport, and the area's main seaport, are located. Other satellite cities include such as Ilsan (to the north), Gwacheon and Anyang (to the south).