Iron Bridge over the Ping River in Chiang Mai (Thailand)

In ancient Sukhothai there lived Naang Noppamart, wise girl and the most beautiful creature in the land. Although married to a Buddhist king, she remained true to her Brahmin faith, and at the end of the year she indulged in the Brahminical custom of preparing offerings to  the genii of the river. This she did by creating a small, boat-like structure from banana leaves, known as a “krathong”. She then placed scented incense sticks in the krathong.  Her husband the king  asked her to explain the origins of this little craft. Noppamart told her husband that it was part of her faith to honour the river spirits. The sovereign praised his wife before the vast crowds by the river, who then rushed to follow her example. Soon the Ping river was aglow with the twinkling lights of thousands of krathongs and the air was filled with joy and laughter.

Legend origin of Chiang Mai festival