Is celebrated throughout the Mahayana tradition from the first to the fifteenth days of the eighth lunar month. It is believed that the gates of Hell are opened on the first day and the ghosts may visit the world for fifteen days. Food offerings are made during this time to relieve the sufferings of these ghosts. On the fifteenth day, Ulambana or Ancestor Day, people visit cemeteries to make offerings to the departed ancestors. Many Theravadins from Cambodia, Laos and Thailand also observe this festival.
Ulambana is also a Japanese Buddhist festival known as Obon, beginning on the thirteenth of July and lasting for three days, which celebrates the reunion of family ancestors with the living.
