The trick to a meaningful U.S. national park visit? See the main attractions, but spend most of your time beneath the well-trodden surface. Here are eight national park excursions that will steer you away from the general public and into the heart of some of the most mind-blowing natural landscapes in the United States.

Glacier National Park has over 745 miles of maintained hiking trails.
Glacier National Park
Activity: Camp to combat climate change

The U.S Geological Survey estimates that this park’s namesake glaciers will exist only in memory by 2030; all the more reason to see them now, but don’t just show up—have your visit raise money for organizations dedicated to fighting glacier-melting climate change in Montana and beyond. The nonprofit Climate Ride hosts an annual five-day hiking adventure that takes you to the most scenic parts of the park—among them Grinnell Glacier, Going-to-the-Sun Road, Many Glacier Valley, and Two Medicine Valley—led by guides who are well-versed in glacial climatology. By night you sleep in pre-pitched tents and enjoy food from a Climate Ride chef. On day five of the fundraising expedition, you’re rewarded for your hiking and good deeds with a day off your feet—a rafting journey down the Flathead River to Glacier National Park’s west entrance. Minimum $3,000 fundraising commitment ($100-300 registration fee; event dependent)
Great Smoky Mountains National Park straddles the border between North Carolina and Tennessee.
Great Smoky Mountain National Park
Activity: Great Smoky–style glamping

Great Smoky Mountain National Park has one of the world’s best-preserved deciduous forests, the oldest mountains in the United States, and more annual visitors than any other national park in the country. The thing is, most tourists only drive through the 384 miles of scenic asphalt that bisect the park’s wilds. To see more, ditch the car: REI’s 5-day Great Smoky Mountains Adventure guides you along parts of the Appalachian Trail that most day hikers never hit. You’ll trek to the park’s tallest waterfall, summit Mount Cammerer for 360-degree views, go ziplining through old-growth forests, and raft on the Nantahala River. At night, you’ll bunk in one of REI’s signature campsites complete with with cushy tents, cozy cots, and cooking areas capable of serving fine fare you’d never expect to eat in backcountry. From $2,419
The Grand Canyon is 277 miles long, up to 18 miles wide, and more than a mile deep.
Grand Canyon National Park
Activity: Scope out sacred sites

At this famous Wonder of the Natural World you can hike, raft, ride a mule, zoom down a zipline, take a helicopter tour, or just enjoy scenic overlooks. But the best way to get to the heart of this colossal place is to learn about the Grand Canyon’s role as a major sacred site to American Indians. Get your facts firsthand on a three-day Discover Hopi tour with Go Native America. On the first day of your adventure, a Hopi guide will take you to lookout spots along Grand Canyon View Road while explaining the landscape’s role in traditional Hopi beliefs and lifestyle. The next two days are spent in the small, ancestral Hopi villages surrounding the canyon where you’ll see 1,000-year-old petroglyphs and traditional Hopi art—not to mention some of the best stargazing in the United States. From $1,295
Located in southern Alaska, Katmai National Park is famous for its Alaskan grizzly bear population.
Katmai National Park
Activity: Wildlife photography workshops

The world’s largest population of coastal grizzlies live in Alaska’s Katmai National Park. To get a glimpse of them, all you have to do is cruise by, but if you want to spend some quality time near these enormous creatures (plus nab some jaw-dropping photos) it’s worth venturing out with a seasoned wildlife photographer. Natural Habitat Adventures runs small, ship-based photography workshops that take you to remote parts of Alaska’s biodiverse backcountry such as Kodiak Island. Led by naturalists and wildlife photographers, you’ll spend eight days navigating the shorelines of Katmai National Park, photographing Alaskan brown bears, sea lions, puffins, bald eagles, and occasionally even whales and wolves along the way. You can bring your long lens to Alaska’s backcountry, but on this trip you’ll get so close to the animals you probably won't even use it. From $9,295
Together, Canyonlands National Park’s four “districts” make up the area of more than 172 football fields.
Canyonlands National Park
Activity: Navigate natural arches and American Indian ruins

Canyonlands is a postcard-perfect image of the wild American frontier; the largest of Utah’s national parks is a 527-square-mile playground of colorful canyons, mesas, rivers, natural arches, and wide-open vistas. Go deep with O.A.R.S. and spend six days camping and rafting class III-IV rapids on the Colorado River through Cataract Canyon. Float through spectacular canyons, check out petroglyphs and American Indian ruins, conquer rapids, and spend your nights unwinding while gazing up at the Milky Way. From $1,499
Yosemite National Park is revered as the birthplace of rock climbing as a sport.
Yosemite National Park
Activity: Extended eco-tours

According to the National Park Service, about 80 percent of visitors to Yosemite never venture beyond Yosemite Valley, which only makes up a minute percentage of this 1,190-square-mile park. To truly grasp the wonder that turned famed naturalist John Muir into Yosemite’s chief advocate, go a little further down the trail with Incredible Adventures, an eco-tour company based in San Francisco. (It's one of the few outfitters to hold an NPS permit that allows it to give guided hikes in the park.) The three-day Yosemite Camping Tour includes stops at highlights like El Capitan, Half Dome, and Bridalveil Fall, but you’ll go deeper into the sprawling meadows of Yosemite’s rarely seen high country and sequoia forest. At night, you’ll rest in a campsite equipped with on-site showers, tents and sleeping pads, and a communal camp stove and fire pit where group cookouts take place. From $500
Yellowstone’s Grand Prismatic Spring is the largest hot spring in the United States and the third largest in the world.
Yellowstone National Park
Activity: Biologist-led wildlife expeditions

Yellowstone is famous for visually astounding geothermal formations (the landscape is home to more than 300 active geysers) as well as abundant wildlife, including bison, elk, and timber wolves. Wyoming-based Teton Science Schools and their team of biologists-cum-guides lead small-group wildlife-spotting expeditions in safari-style vehicles with pop-tops, where visitors will catch glimpses of some of Yellowstone’s most elusive critters. On seven-day expeditions like the Winter Wolves of Yellowstone Tour, participants and guides venture from the comfort of their hotels to the wilds of the Yellowstone National Park supplied with in-vehicle radio monitors, professional-grade binoculars, and detailed field guidebooks. Of course, the expeditions are organized to “maximize your wildlife experiences while minimizing environmental impact.” From $4,300
Zion Canyon’s depth is more than 2,600 feet.
Zion National Park
Activity: Slot canyon sports

Visitors to Zion National Park will be awestruck by two things: first, the magnitude of the rock formations, canyons, and plant life, and second by the crowds coming to admire it all—especially on popular hiking trails such as The Narrows and Angel’s Landing. Zion Rock & Mountain Guides offer four-hour day trips that take the uninitiated—even the out of shape—to slot canyons off the tourist track where you’ll rappel as much as 80 feet down steep red rock faces. You’ll be as impressed with yourself as with the scenery that surrounds. From $219 

This article originally appeared online in October 2015; it has been updated to include current information.

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