Burning of the Character Big

The Burning of the Character "Big" (大), also known as Daimonjiyaki (Japanese: 大文字焼き) or Daimonji Festival is the Japanese Buddhist ritual of burning wood in the character "Big" (大), typically in the mountain, on the last day of the 4-day Bon Festival to send back to the other world the spirits of the family ancestors that they welcomed on the first day. There are many locations in Japan where this ritual is held.

Source: Wikipedia — Burning of the Character Big (CC BY-SA 4.0)