State: Utah
Area: 1,366 sq km
Created: 1964
Best for… mountain-biking, 4WD-ing, rafting
Why go? The Colorado River isn’t responsible for only the Grand Canyon – in southern Utah, this artistic waterway has carved a dramatic array of rust-red gorges, buttes and pinnacles that have been collected into Canyonlands National Park.
The park comprises four districts. The Island in the Sky, a lofty mesa with magnificent views over the park’s plunging depths, is the most accessible, and easily seen via a scenic drive; this is also where you’ll find the 160km White Rim Road – mountain-bike heaven. The Needles is named for the striped Cedar Mesa Sandstone that dominates the area, and is ideal for day-hikes; there are also several campsites here. The burnt-orange canyons of the Maze are remote and best for wild multi-day 4WD adventures. The River regions offer both calm floats and, below the confluence of the Colorado and Green rivers, more raging rafting.
When to go: Open year-round. Temperatures are most pleasant in spring and autumn; summers are hot and stormy. High water for rafting is May-June.
Plan your trip: Canyonlands is just south-west of Moab, and 400km south of Salt Lake City. Include it in a two/three-week Four Corners roadtrip to absorb the Wild West landscapes and Native American culture of Utah, Arizona, Colorado and New Mexico.
State: Kentucky
Area: 215 sq km
Created: 1941
Best for… cave tours, history, boating
Why go? Welcome to the world’s largest known cave system, 645km of passages, grottoes and underground extraordinariness. Human remains dating back over 4,000 years have been found inside, suggesting man has always been curious; luckily, taking a peep is now much easier.
There is a range of guided cave tours, of differing strenuousness, that visit pits, passageways and rock formations. The six-hour Wild Cave Tour is the most hair-raising, a chance to crawl and squeeze through usually off-limits areas.
For the claustrophobic, the park also offers surface adventures. Paddle on the Green River, which helped sculpt this karst landscape into subterranean Swiss cheese, or explore by bike or on horseback. The Mammoth Cave Hotel offers an in-park alternative to camping.
When to go: Open year-round, though activities vary by season. June-August is busiest.
Plan your trip: Mammoth Cave is 145km south-west of Louisville. You could combine the caves with cool tunes by flying into Cincinnati (Ohio) and out of Atlanta (Georgia), driving via Louisville, Nashville and Chattanooga.