Incheon International Airport is the main international airport serving Seoul, the capital of South Korea. It is also one of the largest and busiest airports in the world.

An international airport is an airport with customs and border control facilities enabling passengers to travel between countries around the world. International airports are usually larger than domestic airports, and feature longer runways and have facilities to accommodate heavier aircraft such as the Boeing 747 and the Airbus A380 commonly used for international and intercontinental travel. International airports often host domestic flights, which helps feed both passengers and cargo into international ones.