If you happened to catch the 2001 film Dogtown and Z-Boys, you might remember the story of how a bunch of ragtag teens in Venice, Calif., would expropriate neglected backyard swimming pools, then drain the water out so they could have a nice cement bowl to skateboard in. “Riding” the pool meant carving paths across the bottom, working up to the rim and then, using momentum to defy gravity, going “off the wall.”
