Korean Holidays Explained
National Foundation Day
In 2026: Sat, October 3Public holiday
See the 2026 holiday calendar →Where it comes from
Celebrates the legendary founding of Gojoseon, Korea's first kingdom, by Dangun.
What people do
Ceremonies are held, including one at Chamseongdan altar on Ganghwa Island, said to have been built by Dangun.
What to say
오늘은 하늘이 열린 날, 개천절이에요.oneureun haneuri yeollin nal, gaecheonjeorieyo.Today is Gaecheonjeol — “the day the sky opened.”
Frequently asked questions
What is National Foundation Day in Korea?
National Foundation Day (개천절): Celebrates the legendary founding of Gojoseon, Korea's first kingdom, by Dangun.
When is National Foundation Day in 2026?
In 2026, National Foundation Day falls on Saturday, October 3. It's a public holiday in Korea.
What do Koreans do on National Foundation Day?
Ceremonies are held, including one at Chamseongdan altar on Ganghwa Island, said to have been built by Dangun.
What do people say on National Foundation Day?
A typical line is “오늘은 하늘이 열린 날, 개천절이에요.” (oneureun haneuri yeollin nal, gaecheonjeorieyo): Today is Gaecheonjeol — “the day the sky opened.”