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During the Joseon Dynasty, the royal guards were responsible for guarding and patrolling the gates of the capital city and the royal palaces. The royal palace guards, who were known as the "Wanggung Sumunjang", had the very important duty of protecting the king by guarding the entrance gates of the primary royal palace where the king resided. They were in charge of opening and closing the palace gates, inspecting all visitors, and maintaining a close surveillance of the palace. They were divided into day and night shifts, and the Changing of the Guard ceremony took place whenever the shifts changed over. 

In the late period of the Joseon Dynasty, the Changing of the Guard ceremony was conducted at Deoksugung Palace as at that time Deoksugung was the primary royal palace and the king then resided there. The Changing of the Guard ceremony was originally conducted at Gyeongbokgung Palace in the early Joseon period, but was moved to Deoksugung when Deoksugung was made the primary royal palace after Gyeongbokgung was burned down during the Imjin Invasions of 1592 - 1598. 

After some extensive historical research, this splendid and elegant traditional Korean royal court cultural ceremony was first re-enacted in 1996 and has been a must-see among Seoul's tourist attractions ever since. This ceremony is a great opportunity to experience a rare traditional scene in Korea, as the ceremony is reenacted exactly as it used to be held, with guards wearing royal uniforms, carrying traditional weapons and playing traditional instruments. A tradition comparable to the Changing of the Guards at Buckingham Palace, this ceremony takes place three times a day in front of Daehanmun, the main gate of Deoksugung at 11:00, 14:00, and 15:30 p.m. (except for on Mondays).

The Changing of the Royal Guard at Deoksugung starts with two mounted soldiers leading the way, and a total of 78 Sumungun making an appearance, led by the Sumunjang in the order of Sumunjang, Sumungun, Sungjeongwon Juseo, Aekjeongseo Sayak and Chwiracheok. Once all the Sumungun have arrived with the drumbeat of the Chwiracheok (a military band), it marks the beginning of the changing ceremony.