Kosong is a port city of the North Korea, located on the sea of Eastern Korea (also called Mer of the east and, by the Japan board, Mer of Japan). Kosong is one of the main cities of the province of Kangwon.

A ship of the company Hyundai Asan establishes the connection between the South Korea and Kosong, where unload the South Korean tourists visiting the Kumgang mounts (in Korean: Kumgangsan).