The first recreational runs of whitewater rivers was done in the 1920's in a folding kayak. Ever since, people have taken up the sport and began running whitewater previously thought un-navigable!
Currenty, the world record for tallest waterfall ever kayaked off of is held by Tyler Bradt. He set this when he successfully kayaked off of the 186ft tall Palouse Falls in Washington Sate.
It won't be long until someone else takes the first run down the next exciting, undiscovered stretch of whitewater!