Seoul is the capital of South Korea and is located on the Han River in the country's northwest. The city is situated about 50 km south of the North Korean border, also known as the demilitarised zone (DMZ). Seoul is an ancient city, having served as the historic capital of the Baekje Dynasty (18 BC – 660 AD) and the Joseon Dynasty (1392-1910). The city became the capital of South Korea following the establishment of the South Korean government in 1948. With over ten million people, Seoul is South Korea's largest city and one of the largest cities in the world in terms of population. Covering an area of only 605 square kilometres, smaller than London or New York City, it is one of the world's most densely populated majot cities. Seoul is also one of the world's most digitally-connected places with more internet users than in many other countries. The city is considered one of the top 20 "world-class cities".

The Greater Seoul metropolitan area, which includes the major port city of Incheon, has almost 23 million inhabitants, making it the second most populous metropolitan area in the world, after Greater Tokyo. Almost one half of South Korea's entire population lives in the Greater Seoul area, making it the country's political, cultural, and economic centre, as well as a centre for international business. The city has always played a key role in South Korea's economic development and has been referred to as the ‘Miracle on the Han River’.