The festival where people honor their ancestors with bamboo lanterns in Japan is known as Obon. This Buddhist tradition, usually held in mid-August, involves various rituals to honor deceased relatives. During this time, families return to their hometowns, hold memorial services, and set bamboo lanterns afloat in rivers or oceans to guide spirits back home. Obon emphasizes respect for ancestors and the cycle of life, promoting a deep connection to family.