Attend the Yi Peng Festival During Loy Krathong
If you are in Chiang Mai during the Loy Krathong period which is around the end of October and the beginning of November, you will be able to attend the famous floating lantern event, the Yi Peng Festival in Chiang Mai. The local event often takes place in front of the Three Kings Monument where they will close off the road and bring out the volunteers to perform the local dance. You will also get to see several performances by local universities students which often consisted of traditional folk dances, music, and parades.
There's so much happening at this event that it can easily occupy your hours to see them all. The local Yi Peng event usually starts at 6 PM and goes on until 11 PM. You can also go to the rivers and float your Krathong out into the water, which is how Loy Krathong is usually celebrated all over the country except that in the north, they also let go of the floating lanterns.