Boulder Creek, Colorado
A crisp dunk in Boulder Creek will feel well deserved after hiking up nearby Sugarloaf Mountain. Locals here like to start by jumping in the old fashioned way, grabbing hold of a rope swing (located around the middle of the three-mile creek) and flying through the air with a "woo hoo!" as onlookers clap at the backflips and flubs. This popular spot in Eben G. Fine Park has some faster-paced pockets and dips where you'll need to hold on tight to those beer cans. But rocky embankments and crescents of sand provide ample space for a time-out in the sun. To escape the crowds, kids, and dogs, book a rafting outing on the Upper Colorado River through the St. Julien's new Build Your Own Adventure package, organized by Colorado Wilderness Rides and Guides. The full-day trip ($250/pp) includes gear and transportation from the St. Julien hotel — conveniently located near Eben G. Fine Park.
Rental: If you're going to Boulder Creek, buy a solid two-handled tube for $26 at Whitewater Tube Co. or a standard (yet prone-to-flipping) rubber inner tube for $15 at the nearby Conoco gas station at 1201 Arapahoe Ave.