Floating down the Guadalupe River
on an inner tube
It's a favorite pastime in Central Texas. If you only know Texas through the movies, or newsreels of the life of George Bush, it might seem odd, but the Guadalupe ("Gwadaloopy", or "Gwadaloop") from the Canyon Lake dam down to New Braunfels is a cool green heaven on earth.
The Guadalupe runs crystal clear over rocks that were worn smooth when Columbus was a boy. The banks are deeply lined with oaks, cedars, and cypress, and the "white water" is lively enough to support a local industry of outfitters who will serve you a breakfast of eggs and German sausage before plunking you into the water in a rubber boat.
If you go at spring break time, it's like bumper cars, and if you go in August, you'll bump your butt on the rocks when you don't decide to portage around them, but in springtime in wet years, it can be downright thrilling.
The preferred method for the excursion is to gather a group of compatible people, and a like number of inner tubes, plus one. The extra inner tube floats a big cooler of beer. You, my friend, are expected to turn over, breathe water, and scrape your shins on the rocks, but protect that cooler at all costs.