The Day of the Sun is one of the most important national holidays in North Korea. It is celebrated annually on April 15 and marks the birth anniversary of Kim Il-sung, the country's founding leader. Kim Il-sung ruled North Korea from its establishment in 1948, until his death in 1994. His birthday is considered the 'Day of the Sun' as his name translates to 'become the Sun'.

Festivities on the Day of the Sun are grand and widespread across the country. The day is marked with various events such as art performances, music concerts, and parades. A notable tradition is the Mass Dance, where thousands of people perform synchronous dances in squares and parks. Additionally, Arirang Mass Games, considered the largest performance in the world involving up to 100,000 people, often takes place to coincide with the holiday.

There are other distinctive ways in which the Day of the Sun is celebrated. The Mansudae Grand Monument, a gigantic statue of Kim Il-sung in Pyongyang, attracts a throng of people who lay flowers at its foot to pay homage. Moreover, it is a tradition for North Koreans to visit Mangyongdae, the birthplace of Kim Il-sung. The holiday culminates with an extravagant display of fireworks along the Taedong River in the evening.