Incheon South Korea. Historically and economically a significant place for Koreans. During the Korean War, the city was the site of the Incheon Landing by American forces. Today, it is a metropolitan city with a population of about 2.8 million, politically independent from Seoul. Also, the city serves as a transportation hub by air and sea, with a massive harbor. Several beautiful islands, such as Yeongiong Island and Ganghwa Island, are also within city limits.