
Gaecheonjeol, also known as National Foundation Day, is an official holiday in Korea.
Here’s what Gaecheonjeol is, when it is, and the myth behind it!
Quick Summary
- Gaecheonjeol (National Foundation Day) is a day to commemorate the legendary founding of the first Korean kingdom, Gojoseon.
- Gaecheonjeol is celebrated on October 3rd every year.
- Most Koreans celebrate Gaecheonjeol as a simple day off to relax or spend time with family and friends.
What Is Gaecheonjeol (National Foundation Day)?
Gaecheonjeol (National Foundation Day) is a day to commemorate the legendary founding of the first Korean kingdom, Gojoseon (Old Joseon) founded by Dangun in 2333 B.C.
This holiday is technically not a national foundation day.
According to the National Folk Museum of Korea, Gaecheonjeol literally means “opening sky day” and symbolizes the birth of the Korean race.
When Is Gaecheonjeol?
Gaecheonjeol is celebrated on October 3rd (solar calendar) every year.
It was originally observed on October 3rd of the lunar calendar. But in 1949, it was officially changed to the solar calendar under the Act on National Holidays (Act No. 53, Oct. 1, 1949) to maintain consistency in national celebrations.
And yet, Daejonggyo (Daejongism and Dangunism, which worship Dangun) continues to hold a traditional ceremony at the Chamseongdan Altar of Manisan Mountain on Ganghwa Island according to the lunar calendar.
This annual ritual is an important spiritual event for followers, who gather to pay homage to Dangun, the legendary founder of Korea, reinforcing cultural and historical ties to Korea’s mythical origins.
What Is the Myth Behind Gaecheonjeol?
The holiday is rooted in the creation myth of Korea.
And here’s an excerpt of How It All Got Started from the book, “A Korean Girl Explains: What No One Tells You About Korean Culture.”
According to myth, Dangun was born from the union of a god and a she-bear. Not so weird when you find out why. Hwanung, the son of the supreme deity Hwanin, descended from heaven to Mount Taebaek to bring order and harmony to the human world. He established a city called Shinshi and taught humans skills and gave them knowledge. One day, a bear and a tiger approached Hwanung, expressing their desire to become human. Hwanung instructed them to eat only garlic and mugwort and remain in a cave for 100 days. The tiger gave up, but the bear persevered and transformed into a woman. Hwanung and Ungnyeo (Bear Woman) became the parents of Dangun. And that’s why kids, we eat so much garlic and mugwort!
A Korean Girl Explains: What No One Tells You About Korean Culture
How Do Koreans Celebrate Gaecheonjeol?

Some Koreans spend the day protesting in Gwanghwamun Square, also known as “protest square.”
For example, this recent article titled “Large-Scale Rallies Throughout Downtown Seoul on National Foundation Day… Traffic Congestion,” written by Reporter Park Jun-woo at Munhwa Ilbo, highlights how political and civic groups often hold large demonstrations on this national holiday.
However, for most Koreans, Gaecheonjeol is simply a public holiday.
It’s a chance to relax, catch up on rest, or spend quality time with family and friends.
When we’re lucky enough to get a long weekend from this holiday, many people take advantage to go on short trips, visit parks, or enjoy outdoor activities, especially if the weather is nice.
Some also use the opportunity to reflect on Korean history or watch patriotic programs on TV, though for most, it’s just a welcome break from work.
Although it’s not widely celebrated with large public festivities, Gaecheonjeol is a time for Koreans to reflect on our ancient heritage.
Government buildings display the national flag, and many people enjoy the public holiday as a time to rest or explore Korean history.