An industrial port about 36km (22 miles) west of Seoul on the Yellow Sea, it is home to the country's largest airport, and you will most likely arrive here. Home to almost 2.5 million people, the city warrants its own small subway system (which is conveniently linked to Seoul's system). South Korea's fifth-largest city, it has incorporated almost 150 surrounding islands within its administrative district.
It can be a nice day trip from Seoul, or a stopping point on the way to remote islands or even to China, which may explain how the city houses the country's only official Chinatown within its borders. There is no city center per se, but several hubs with different emphases. The older district is below Jayu Park, with technological and communication centers in the Songdo area. There is expansive housing and industry on the reclaimed harbor front and a shopping district which radiates out from the old post office.
Its beaches and small islands attract many domestic tourists from Seoul on weekends, especially during the warmer months.