The maple tree and birch of Cheonghakseonwon turn red in October. The Maple Tree Festival is held in Samseonggung for 15 days from the middle to the end of October. Gacheondaejae is served on the date of Cheonjae selected during the period of the Maple Tree Festival, the eve is generally held during the weekend, and the Boncheonjae is held on Sunday. Gaecheondaejae is Open Sky Great Gut�� in Korean. When this great Gut is held, the trainees from the nation gather in the main palace, Samseonggung, and hold the various services and events.