National Foundation Day is observed in South Korea every October 3, celebrating the foundation of the ancient Korean kingdom of Gojoseon. This kingdom was established by Dangun Wanggeom, who is said to be the son of a Lord of Heaven and a bear turned into a woman. The founding date of Gojoseon, traditionally regarded as 2333 BC, is considered the birth of the Korean nation. Originally, the holiday included a traditional harvest ceremony, and it was enacted as a national holiday in 1909, later fixed to October 3 in 1949 according to the Gregorian calendar. While National Foundation Day is also recognized in North Korea, it is not a public holiday there, although commemorative ceremonies occur at the Mausoleum of Tangun.