Seoul is located on the basin of the Han River in the country's northwest. The North Korean border is about 50 km to the north.

Seoul first appears in history in 18 BC, when the Baekje kingdom established its capital Wiryeseong in what is now around Songpa-gu, southeastern Seoul. Modern Seoul descends from the Goryeo-era city called Namgyeong, which then became the capital of Korea during the Joseon dynasty.