Southwest Utah's Bryce Canyon boasts a unique beauty, thanks to multi-hued rock formations known as hoodoos. These spire-like formations (ranging from the height of the average person to that of a 10-story building) were created from the erosion of layers of sedimentary rock. Despite its name, Bryce Canyon isn’t actually a canyon, but a series of depressions formed by erosions in the Paunsaugunt Plateau; the largest, Bryce Amphitheater, is 12 miles long, three miles wide, and 800-plus feet deep. Starting and ending at Sunrise point, Queens Garden Trail (1.8 miles roundtrip and one- to two-hours long) is easy to moderate in its difficulty level; it's the easiest way to get you into the amphitheater. 

With three different ecosystems and a maximum of 300 park guests per day, the Cumberland Island National Seashore – located just north of the Georgia-Florida border and only accessible via ferry from St. Mary’s – is perfect for nature lovers seeking quiet and crowd-free exploring. Established as a national seashore in 1972, the island’s beaches, salt marshes, and maritime forests are gorgeous. Willow Pond Trail is 1.5 miles each way and will take you from the rugged coast into the verdant forest. This moderate hike is located about 5.5 miles north of Sea Camp Dock along the Parallel Trail. After beachcombing for sand dollars on the eastern coastline, hikers can trek into a forest of towering oak trees dressed in Spanish moss and encounter an array of wildlife, including wild horses, birds, deer, turkeys, and armadillos.

Covering more than a million acres in northwest Montana, Glacier National Park brims with rich forests, craggy mountains, tranquil lakes, and lush alpine meadows. Close to 270 species of birds and mammals call this park home, including grizzly bears, gray wolves, and golden eagles. With over 740 miles in trails, there's no shortage of options for exploring, but the Grinnell Glacier Trail (hikeable from mid-July through September) takes visitors especially close to the glaciers. It's 5.5 miles each way, starting at Many Glacier Hotel, and takes you up 1,600 feet in elevation to the Viewpoint, where you’ll marvel at three glaciers: Grinnell, Salamander, and Gem. Sadly, the park’s namesake features have disappeared at an alarming rate over the past century: Where once there were over 150 glaciers, today there are only around two dozen. 

Forgo being swept along with the tourist crush that winds its way down Grand Canyon National Park’s popular South Rim thoroughfare, the Bright Angel Trail, in favor of the lesser-trammeled South Kaibab Trail, just east of Grand Canyon Village. The moderate, well-maintained route affords superlative scenery, tracing the canyon’s ridgeline via a series of switchbacks – varying in length from just under a mile to about seven miles – on a steep descent to the Colorado River. 

Laurance S. Rockefeller returned this formerly private, 1,106-acre preserve to the public in 2007, adding eight miles of trails to Grand Teton National Park, about a mile above the Jackson Hole valley. We recommend the primary loop, including trails Lake Creek and Woodland, for its tranquil views and summertime appeal. Locals fancy the shoreline for a run or hike, followed by a splash into the waters from Phelps Lake Rock, a 20-foot high perch midway around the pond. Moose roam this peaceful trail, which winds through the woods before culminating at Phelps Lake. The main route goes to the lake and back, providing expansive mountain views from a series of rest stops. When still, the sapphire waters reflect the craggy Teton peaks. 

Maui's Haleakala National Park is named for its showpiece 10,000-foot Haleakala “crater” (actually an erosional depression), and comprises five different climate zones and amazingly contrasting nature realms of coastal jungles and stark subalpine desert mountains. The Kipahulu District is home to the four-mile Pīpīwai Trail, where freshwater streams meet forest areas with waterfalls and other natural features. At the end of this moderate scenic trek, you’ll have a beautiful view of Makahiku Falls and Waimoku Falls.

A limestone and sandstone labyrinth lurks beneath the rolling hills of Kentucky’s Mammoth Cave National Park, home to the world’s largest known cave (the current surveyed distance is 400 miles, though scientists estimate the subterranean complex extends for as many as 1,000 miles). Intrepid explorers can walk through this fascinating underworld, which inspired Ralph Waldo Emerson’s transcendental appreciation of nature, on the Star Chamber Tour, a guided, evening hike ($20). The moderate hike is 1.5 miles roundtrip and you'll wander into the “hospital,” where 19th-century cave owner Dr. John Croghan treated tuberculosis patients, convinced the cool underground air was healing, and the namesake Star Chamber, which creates an illusion of the night sky.

The cliff dwellings at Colorado's Mesa Verde National Park are among the best preserved in North America. Occupied for about 100 years between the late 1190s and 1300 by Pueblo Indians, these sandstone brick structures were built with wooden beams and mortar; some contain just one room while others are massive complexes resembling mini-villages. Cliff Palace is by far the largest dwelling at Mesa Verde, with 150 rooms believed to have housed a population of about 100 people. On the strenuous hour-long ranger-led trek to Cliff Palace, you’ll climb ladders, explore kivas (religious ceremonial chambers), and learn about how the Pueblos lived.

With 101 miles of Appalachian Trail, Shenandoah National Park is an ideal compromise for hikers who want to trammel the legendary, 14-state path but can’t commit to the half-year the 2,200-mile journey demands. Though the Appalachian Trail sections at Shenandoah don’t delve as deep into the wilderness as the park’s remaining 399 miles of paths, the historic route offers plenty of opportunities to take in the many shades of the Blue Ridge Mountains – and supplies serious bragging rights. Skyland, the lodge-to-lodge section of the Appalachian Trail, skirts the famed Skyline Drive and affords sweeping views of the mountains’ hazy hues.

Natural attractions at California's Yosemite National Park are bountiful: Half Dome, one of the park’s hallmark rock formations, towers 5,000 feet above the valley floor; Horsetail Fall, a cascade that reflects the sunset and turns a fiery shade of red in February; and Glacier Point, an overlook with expansive views of the park. Yet the appeal of giant sequoias – almost fantastical in their proportions, with trunks wide enough for cars to pass through – is irresistible. Hike to Mariposa Grove along the Outer Loop Trail (6.9 miles roundtrip) where there are some 500 mature sequoias. Just under a mile from the parking lot sits the 1,800-year-old Grizzly Giant, one of the largest in the grove, and the California Tunnel, a sequoia cut in 1895 to allow carriages to pass through. Continuing on the hike reveals the Faithful Couple, two sequoias fused together at their trunks like conjoined twins, and the Clothespin Tree, a giant with a hollowed out trunk resting on two slender legs, resembling its namesake.