Tado-gawa river, which Tado-yama mountain is its origin, is used to make a pool in the mid July. The swimming pool is free for public, and its feature is that the river is dammed. The natural float of water keeps the river clean. There is 80cm of water, and its temperature is between 18 to 20℃, so it feels very cool in summer.
It is a popular sightseeing spot where the local people also love.
[Website of TripAvisor]
https://www.tripadvisor.jp/Attraction_Review-g651657-d3610325-Reviews-Tado_Valley-Kuwana_Mie_Prefecture_Kinki.html