Fukagawa Hachiman Matsuri in Tokyo
Fukagawa Hachiman Matsuri, one of the three great festivals of Edo tracing to around 1642, is known as the mizu-kake matsuri, or water-throwing festival, for the tradition of dousing passing mikoshi with water as relief from summer heat. Held at Tomioka Hachimangu, the full-scale Hon Matsuri with more than fifty mikoshi occurs once every three years amid smaller annual observances.
Fukagawa Hachiman Matsuri traces its origins to shortly after Tomioka Hachimangu's founding in 1627, with the festival itself commonly dated to around 1642, making it one of the oldest of the three festivals collectively known as the great festivals of Edo alongside Kanda Matsuri and Sanno Matsuri.