Kloofing is a uniquely Western Cape sport. Well, at least the name is unique - in the rest of the world they call it Canyoning. The Cape mountains, warm climate, cold mountain water and hard quartz sandstone have come together to form the unique river gorges and valleys which make great kloofing possible.
Kloofing involves getting yourself down a river gorge - one that is fast-flowing, but with too little water for kayaking or any other boating. Sometimes you just boulder-hop, sometimes you wade, or swim, sometimes you have to climb, and many kloofs have "compulsory jumps" from an insane height.
Some things set kloofing apart from ordinary hiking: there is no path, so you have some freedom to choose your own route and challenge yourself with the obstacles along the way. You're always constrained by the sides of the gorge, so it's hard to get lost in a kloof, but there is an enormous freedom to explore: tributaries, waterfalls, potholes, jumps, or just to stop at a perfect pool for a three-hour lunch break.