Wikipedia
Feast of Lanterns
Pacific Grove, California's Feast of Lanterns is an annual celebration, over 100 years old, of the legend of the Blue Willow, a fabricated " Chinese" story. However, in Pacific Grove's version of the story, the fleeing couple turns into Monarch Butterflies (because Pacific Grove likes to be known as "Butterfly Town, USA"), as opposed to birds, to flee the evil Mandarin.
Usage examples of "feast of lanterns".
Every year at the Feast of Lanterns, he bore the whole expense of decorating the quarter and went about giving candy to small children.