Stems from the time when Lord Buddha's Footprint was found in the reign of King Songtham of Ayutthaya. The mondop was built to cover the footprint. At present, the footprint is situated at Wat Phra Phutthabat Ratchaworamahawihan, Tambon Khun Khon. A large number of Thais and foreigners come to Phra Phutthabat during the event. The event is held twice a year: from the first day till the fifteenth day of the waxing moon in the third month of the lunar calendar totalling 15 days; and from the eighth day until the fifteenth day of the waxing moon in the fourth month of the lunar calendar for 8 days.