Meadow Run (Ohiopyle State Park, PA)
Credit: Michael P Gadomski / Getty Images

This slide is colossal: a long, fast chute that twists and drops through slabs of bedrock where Meadow Run dumps into the Youghiogheny River in the rolling Laurel Highlands (only a few miles from Frank Lloyd Wright's masterpiece Fallingwater). The stream gets pushy after heavy rains, making for a freakishly fast ride, but even on an average day the flume will hustle you 200 feet or so, in a spray of whitewater, into one of many shallow pools.