Taking place on the grounds of Isakiji temple, a branch of Mount Hiei's Enryakuji temple, the ascetic ritual consisted of the monks jumping in the lake one by one, in the hope that the act of throwing their bodies -- which in Japanese can also mean "risking one's life" -- into the water would grant the wishes of others.
The dozen monks, aged between 28 and 44, have completed a 100-day practice known as "kaihogyo" (circling the mountain), at Enryakuji temple at Mount Hiei in the Shiga Prefectural city of Otsu.
In the "Isaki-no-saotobi" (jumping from a beam at Isaki) ritual held overlooking Lake Biwa on Aug. 1, the monks walked to the edge of the beam, about 13 meters long, before plunging into the water below while putting their hands together in prayer.
The ritual is believed to have started in the Heian period, with a history stretching back about 1,100 years. At this year's event, approximately 200 worshippers looked down toward the jumping monks from a temple hall located above the beam.
Koshun Haba, the 44-year-old chief priest of Tenporinji temple in Tottori Prefecture, who took part, said, "With so many regions in Japan being badly affected by water due to heavy rains, I pray for people's future safety by throwing myself into Lake Biwa, a symbol of bountiful water."