Utah's Zion and Bryce Canyon national parks illustrate the diverse terrain and geological splendors of America's top national parks. But if you want to see these two marvels without rubbing shoulders with other visitors, you're going to need to take a different approach. "Millions of people visit Zion, but relatively few go exploring into the park's secret places," says Janice Holly Booth, author of the book "Only Pack What You Can Carry: My Path to Inner Strength, Confidence and True Self Knowledge," a book published by National Geographic. Instead of hiking on the popular trails with the masses and venturing to well-traversed parks like the iconic Arches National Park, immerse yourself in the backcountry and remote spots to enjoy seclusion and stunning scenery. To help you plan an outdoor adventure to remember, U.S. News pinpointed little-known gems in Utah's iconic national parks that merit a visit all on their own.

Mossy Cave

Bryce Canyon National Park, Utah

Outside the main park at Bryce Canyon is a trail that leads to the "mossy cave," an ideal trail for children that's not long or strenuous. The trail snakes along a creek and leads both to the cave and a waterfall. You can also enjoy the characteristic "hoodoos" of Bryce Canyon National Park, or spires of red rock formed by weathering and erosion. Most visitors stop at the cave and large waterfall not realizing even more beauty exists beyond. Travel along the creek farther back along a flat path for even more breathtaking landscapes featuring several small waterfalls cut into the rock and a slice of Bryce's backcountry that still feels largely undiscovered.

Peek-A-Boo Loop Trail

Bryce Canyon National Park, Utah

Within Bryce Canyon's main park, you'll find many different hiking trails leading into the canyon that intersect with one another, allowing hikers to hop on and off various trails for a tailored experience. While most of these trails are filled with visitors, Booth says her go-to trail in Bryce is the Peek-A-Boo Loop, which leads further into the canyon itself. "The trail offers all the visual rewards of the more crowded trails – hoodoos, walls and arches – but in a more expansive and open environment," Booth explains.

The Narrows

Zion National Park, Utah

The Narrows are one of the most popular areas within Zion, because the hike takes you through Utah's dramatic slot canyons. But there is a different way to tackle the Narrows, according to Melanie Tucker, owner and chief designer at adventure tour operator Rare Finds Travel. She recommends starting from the opposite direction; at this end, the slot canyons are only visited by a handful of people each day, she says. Tucker also recommends using Zion Rock & Mountain Guides to drop you off at the Chamberlain's Ranch Trailhead. You then "head down the river creek-stomp style, into and through Zion Canyon and end up, 16 miles later, at the end of the canyon road where the Zion shuttle bus can pick you up and take you back down to the visitors center," Tucker says, emphasizing that the journey is a strenuous hike through knee-deep water. "It's a life-changing day," she says.

The Backcountry

Bryce Canyon and Zion National Parks, Utah

For solitude in both national parks, travel to the backcountry. These lesser-visited destinations are off the map for most tourists and transport you into the wilderness; though if you'll be camping overnight, you will need to secure a permit from each park. Bryce offers two main trails in the backcountry, which hikers can split into sections if desired. The Under-the-Rim Trail runs nearly 23 miles, but can be divided into between 4- and 11-mile segments. The Riggs Spring Loop is another option at nearly 8 miles that winds past fir, spruce and bristlecone forests with phenomenal views along the way. In Zion, more than 80 percent of the park, or 124,000 acres, is designated as wilderness. This area, too, is seeing an increase in visitor interest. The National Park Service recommends booking permits as soon as they are available, up to three months in advance of your trip.

Kolob Canyons is another backcountry area of Zion worth exploring. The park offers a respite from the crowds, Booth says, noting that she's only ever encountered one person on its Double Arch Alcove Trail. Clem Bason, CEO of goSeek.com, agrees with its remoteness. "When we were there, a ranger closed one of the side trails due to a cougar wandering around," he says, and recommends the Taylor Creek Trail. "You get the traditional box canyon. You get the creek. You get some vintage homesteads. And you get it all in about four hours," he adds.

Leslie Harvey, who blogs at TripsWithTykes.com, says her family traveled to a lesser-known trail in the backcountry after a tip from a guide. Locals call it Many Pools, Harvey explains. It's located at the east side of the park at an unmarked trailhead. "It's best done during or right after rain when waterfalls are abundant," Harvey says, adding, "It requires a decent level of physical fitness and non-slip shoes or hiking boots," as hikers will need to climb over slick rocks.

Another way to see a large swatch of the backcountry (if you don't want to hike) is to take a jeep tour. "If you want to see almost nobody other than the occasional other four-wheel [drive] Jeep, then take the full-day backcountry jeep tour [with Zion Rock & Mountain Guides] into East Zion," Tucker says.

"If you really want to see Zion and beat the crowds, the best way is to hire a guide and go canyoneering," Booth says. "There is no better way to see the hidden and exquisite places in Zion than with a harness and rope," she adds.

Cool Sand Dunes State Park; Kodachrome Basin State Park

Utah

Another great option to enjoy the unparalleled red rock and mesa scenery that is southern Utah without the crowds is to make time to visit some under-the-radar state parks. A fraction of the people visit these splendid Utah marvels that offer similar landscapes. In southern Utah, check out Coral Sand Dunes State Park, which is close to Zion and offers visitors the chance to try sandboarding on enormous sand dunes, or Kodachrome Basin State Park, located near Bryce Canyon National Park, which offers scenic trails, arches, rocks and 360-degree mesa views.

Grand Staircase-Escalante National Monument

Utah