Yi Peng is the Lanna festival of lights held on the full moon of the 12th lunar month, estimated November 14-16, 2026. Thousands of khom loi (paper lanterns) are released into the sky. In Chiang Mai, Yi Peng coincides with Loi Krathong where decorated floats are set adrift on the Ping River. Key events: CAD Mass Lantern Release at Mae Jo (3,500-5,500 THB tickets, sells out by August), official ceremony at Wat Phan Tao (free), Tha Phae Gate festival (free, multi-day), Loi Krathong at Nawarat Bridge (krathong 50-200 THB), and temple ceremonies across Old City. Essential tips: book CAD tickets months early, accommodation 2-3 months ahead, watch for falling lanterns, respect Buddhist ceremonies.