https://www.landearth.co.jp/en/ the First company to bring white water rafting to this river and it is still the best for Canyoning and White water Rafting. Check them out, they are the best and the originals on this river .
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https://www.youtube.com/watch?v=xrp8Gc6guQY
Seven Sisters Springs at the Chaz in Florida ! This was so cool you could go down about 10 to 15 feet into these holes and swim through these caves to the next opening. Since it was spring water it was clean , clear, and Pretty. 6 of the 7 caves/holes is easily doable, but ONE I would NOT recommend trying , much too tight , I almost got stuck in it. In any case it was sooo much fun to kayak to this place and swim in these underwater caves. with Get Up and Go Kayaking - Chassahowitzka
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https://www.youtube.com/watch?v=iTsx-fPZ_3M