Urban pools are usually rectangular holes in the ground made of concrete and filled with chlorinated water (and sometimes leaves, lost toys and empty Cheetos bags). But when Denver Parks and Recreation decided to remake the outdoor pool next to the La Alma Recreation Center, which sits in a neighborhood chock-full of kids, it went far beyond an ordinary rectangle. Though there are still six lanes where lap swimmers can front-crawl calories away, the pool also sports a diving board and a twisty-tunnel water slide so tall that adults brave enough to give it a whirl have been known to whoop with joy when the ride is over. The pool also has an exemplary kiddie area, complete with things that rain water down, things that spit water up, a padded toddler slide and a freaking whirlpool — which is big enough for grownups, too. Not that we'd know or anything.