The Fukagawa Hachiman Matsuri is one of the three biggest Edo festivals held in Tokyo, along with Sanja Matsuri and Kanda Matsuri.
Nicknamed mizu-kake matsuri—literally water throwing festival—you will soon understand its meaning, where people throw water on the mikoshi, the portable shrines carried in the district. From local shopkeepers to firefighters, everybody is happily throwing water to the mikoshi.
Though an annual event, the festival is celebrated at full size with a Hon-matsuri every three years (2020; 2023; 2026; etc.). For the occasion, over 50 mikoshi are carried in the streets.
The Tomioka Hachiman-gū, the host of the festival, is also known to have the heaviest mikoshi in the Kantō region, weighing 4.5 tons. It is decorated with diamonds, sapphires and rubies, and is worth over a billion yen. It is so heavy that it is not usually carried in the street, but is on display at the shrine.
If you are not scared of huge crowds don't miss the event, to see the mikoshi or to enjoy some street food. The event is five days long, with taiko, koto and dance performances.