National Foundation Day in South Korea Date in the current year: October 3, 2024

Gojoseon was founded by Dangun Wanggeom (another name is Tangun), the son of a Lord of Heaven and a bear turned into woman. He ascended the throne of his father and built a new capital Asadal. The new kingdom was called Joseon, that is now known as Gojoseon (“go” means “ancient” and it helps distinguishing Gojoseon from Joseon, that was founded much later). The date of foundation of Gojoseon in 2333 BC is traditionally regarded as the date of foundation of the Korean nation.

Original celebration of this holiday included traditional Korean harvest ceremony, but in 1909 the day was enacted as a national holiday. It was celebrated on the third day of the tenth month of the lunar calendar. In 1949 the date was fixed to be on October 3 according to the Gregorian calendar.

National Foundation Day is also recognized in Northern Korea, but it's not a public holiday. An annual commemorative ceremony takes place at the Mausoleum of Tangun.