ARCHES NATIONAL PARK
Moab, Utah / 76,519 acres
Your best (and perhaps only) bet for solitude in this popular park: Get up at dawn and HIKE the six-mile Devil's Garden loop trail over slickrock and sagebrush scruband past five of the park's namesake sandstone archesto see 306-foot-tall Landscape Arch illuminated at sunrise.
BADLANDS NATIONAL PARK
Interior, South Dakota / 242,756 acres
Make the Sage Creek Campground in the west end of the park your base for DAY HIKES in the trailless, 64,000-acre Sage Creek Wilderness Areathe park system's largest mixed-grassland prairie, filled with pronghorn antelope, bighorn sheep, and bison.
BIG BEND NATIONAL PARK
Big Bend, Texas / 801,163 acres
The ten miles of prickly-pear-and-cholla-cactus-lined trails atop Mesa de Anguila, in the park's rugged western reaches, are a BACKPACKER'S DREAMchallenging and remote. Unless you're a rattlesnake, avoid the scorching summer sun.
BISCAYNE NATIONAL PARK
Homestead, Florida / 172,924 acres
DIVE or SNORKEL the 85-degree waters off quiet Shark Reef in the southeastern corner of this marine playground (the park is 95 percent water), and you'll spot corals, Kool-Aid-colored parrot fish, and the occasional harmless nurse shark.
BLACK CANYON OF THE GUNNISON NATIONAL PARK
Montrose, Colorado / 29,927 acres
CROSS COUNTRY-SKI the six-mile South Rim Road from Gunnison Point to High Point Overlook (it's closed to traffic December-March) for dizzying views of the 2,000-foot-deep, marblelike gneiss canyonbut none of the RVers that swarm the park each summer.
BRYCE CANYON NATIONAL PARK
Bryce Canyon, Utah / 35,835 acres
Gawk at the multicolored sandstone spires and pinnacles towering up to 150 feet from the seldom-traveled Riggs Spring Loop, a nine-mile HIKING trail from Yovimpa Point, over sun-bleached plateaus, and through a Ponderosa pine forest, to Rainbow Point.
CAPITOL REEF NATIONAL PARK
Torrey, Utah / 241,904 acres
You'll MOUNTAIN BIKE past sandstone monoliths and high-desert prairie grasses on the Cathedral Valley Loop, a challenging, 60-mile network of jeep trails in the park's northern end. Be prepared to share the road with 4WD vehicles and other experienced cyclists, though it's doubtful you'll see many of either.
CARLSBAD CAVERNS NATIONAL PARK
Carlsbad, New Mexico/ 46,766 acres
Want to get your belly dirty? Venture beyond the Big Room and snag a spot on the Sunday-afternoon ranger-guided SPELUNKING tour of Spider Cave, a three-mile-long maze of wormlike helictites, giant blue-green stalactites, and ver-r-ry tight squeezes.
CHANNEL ISLANDS NATIONAL PARK
Ventura, California / 249,561 acres
Paddle a SEA KAYAK through 80-by-40-foot Painted Cave on the north shore of Santa Cruz, the largest of the five wildlife-rich Channel Islands, and quietly shine your headlamp on multicolored rock formations, lichens, and algae while sea lions bark in the shadows.
CRATER LAKE NATIONAL PARK
Crater Lake, Oregon / 183,224 acres
HIKE the Pacific Crest Trail and steep Union Peak Trail 12 miles round-trip to the summit of Union Peak, at 7,709 feet one of the highest points in the park, to find sweeping vistas of the crater rim and Southern Cascadesand a fraction of the foot traffic you'd encounter on neighboring Mount Scott.
CUYAHOGA VALLEY NATIONAL PARK
Brecksville, Ohio / 32,859 acres
A HIKE on the gently sloping eight-mile stretch of Ohio's 1,200-mile Buckeye Trail from the Station Road Bridge to the Cuyahoga River is about as strenuous as it gets in the state's only national park, established in the fall of 2000. Catch peak foliage in mid-October.
DEATH VALLEY NATIONAL PARK
Death Valley, California / 3.3 million acres
Bring a full CamelBak when you MOUNTAIN BIKE the 26-mile end-to-end Titus Canyon jeep road through the northeast corner of this arid park. After two 5,000-foot climbs in the Grapevine Mountains, things flatten out in The Narrows canyon. The temps are coolest from November to April.
DENALI NATIONAL PARK AND PRESERVE
Denali Park, Alaska / 6.1 million acres
Explore some of the most remote glaciers in Denali on a six-day basic MOUNTAINEERING course with the Alaska Mountaineering School (from $1,350 per person; 907-733-1016, www.climb alaska.org). You'll cover route finding, ice climbing, and crevasse rescue.
DRY TORTUGAS NATIONAL PARK
Key West, Florida / 64,701 acres
Load a KAYAK and your binoculars onto the ferry from Key West. You'll spot nesting sooty terns and soaring frigate birds, but very few other paddlers, as you explore this remote cluster of palm-covered keys and shallow reefs some 240 miles southwest of Miami.
EVERGLADES NATIONAL PARK
Homestead, Florida / 1.5 million acres
Spend seven to ten days CANOEING or KAYAKING the mangrove-lined, 99-mile Wilderness Waterway, which winds north-south through southern Florida's marshlands and is filled with gators, snowy and great egrets, and manatees. Hate skeeters? Go in January or February.
GATES OF THE ARCTIC NATIONAL PARK AND PRESERVE
Bettles, Alaska / 8.5 million acres
Fly from Bettles to Circle Lake, in the park's southwestern corner, and spend a week BACKPACKING (and bushwhacking) among the granite spires of the isolated, 7,000-foot Arrigetch Peaks. Backcountry navigation skills are a must.
GLACIER BAY NATIONAL AND PRESERVE
Gustavus, Alaska / 3.3 million acres
The only sounds you'll hear as you sea kayak among 5,000-foot peaks in the fjords of icy Muir Inlet are lapping waves, barking sea lions, and the occasional crash of ice calving off the Riggs and McBride Glaciers. Go June through mid-July, when the northern end of the Inlet is closed to motorboats.
GRAND CANYON NATIONAL PARK
Grand Canyon, Arizona / 1.2 million acres
Hone your backcountry skills on one of 50-plus educational trips offered March-November by the Grand Canyon Field Institute (www.grand canyon.org/fieldinstitute). Try the eight-day North Bass to Modred Abyss trip and you'll backpack and canyoneer some of the toughest terrain in the park.
GRAND TETON NATIONAL PARK
Moose, Wyoming / 309,995 acres
CLIMB ten-pitch, 5.7-rated Serendipity Arete on 12,928-foot Mount Owen and get jaw-dropping views of the Grand Teton's southwest face. Bonus: The full-day hike in to Valhalla Canyon keeps the rock-monkey masses at bay.
GREAT BASIN NATIONAL PARK
Baker, Nevada / 77,180 acres
Spend two days BACKPACKING the glacier-carved highlands. From Baker Creek Trail, head south across the isolated ridgelines of Mount Washington (11,676 feet) and Lincoln Peak (11,597 feet), then into Decathon Canyon. You'll need good navigation skillsthere are few trailsand enough sense to take cover during storms.
GUADALUPE MOUNTAINS NATIONAL PARK
Salt Flat, Texas / 86,416 acres
HIKE the steep (you gain 3,000 feet), rugged Guadalupe Peak Trail to the highest point in Texas8,749-foot Guadalupe Peakfor hundred-mile views of the West Texas canyonlands. It's an eight-mile round-trip. Go in April and May, when the cacti are in bloom.
HALEAKALA NATIONAL PARK
Makawao, Hawaii / 29,830 acres
The two-day, 18.4-mile end-to-end HIKE on the Sliding Sands and Kaupo Gap Trails takes you from the barren Haleakala summit, at 6,380 feet, through four wildly different ecosystems to the verdant oceanside hamlet of Kaupo (elevation 240 feet) outside the park. Hard on the kneesbut worth it.
HAWAII VOLCANOES NATIONAL PARK
Volcano village, Hawaii / 209,695 acres
HIKE across hardened mounds of black lava and through forests of tree ferns and koa on the Napau Trailwith views of the Pacific below and Mauna Loa above. Camp at Napau Crater under the glow of Puu Oo, an active, dangerous cinder-and-spatter cone. It's a seven-mile hike, one-way.
HOT SPRINGS NATIONAL PARK
Hot Springs, Arkansas / 5,500 acres
Yellowstone it ain't44 of the park's 47 thermal springs have been channeled into reservoirs that feed turn-of-the-century bathhouses. Take the requisite SOAK, then hightail it ten miles to the top of 1,405-foot Music Mountain via the Sunset Trail.
JOSHUA TREE NATIONAL PARK
Twentynine Palms, California / 1.02 MILLION acres
With dozens of granite buttresses and two hulking domes, the Comic Book area, 600 yards west of the Barker Dam turnoff, offers plenty of CLIMBING routes, from Welcome to Joshua Tree, a two-pitch 5.10c with a view, to Alice in Wonderjam, a splitter 5.9 crack. And there's no waiting in line.
KATMANI NATIONAL PARK PRESERVE
King Salmon, Alaska / 4.1 million acres
You don't book a cabin at Kulik Lodge, on the shores of 51-square-mile Nonvianuk Lake, to be pampered. You come to ANGLE for 45-pound king salmon (July) and ten-pound rainbows (September). For reservations, call Katmailand Inc. (800-544-0551).
KENAI FJORDS NATIONAL PARK
Seward, Alaska / 669,983 acres
KAYAK with harbor seals and orcas, or fish for monster halibut if you dare (they grow up to 400 pounds) on the glassy waters of Nuka Bay, a 45-minute flight southwest from Seward. Reserve the area's primitive, lone cabin, on the North Arm.
KOBUK VALLEY NATIONAL PARK
Kotzebue, Alaska / 1.8 million acres
The hundred-foot-tall Great Kobuk Sand Dunes offer bird's-eye views of migrating caribou in August and September. Reach them on an 80-mile, ten-day RAFT or CANOE trip down the Class II Kobuk River from the native village of Ambler.
LASSEN VOLCANIC NATIONAL PARK
Mineral, California / 106,372 acres
An easy, 4.4-mile round-trip HIKE on the Devil's Kitchen Trail takes you past the weird geothermal features Lassen is known forcinder cones, hissing fumeroles, and boiling mud potswithout the crowds you'll find on the Bumpass Hell Trail.
MAMMOTH CAVE NATIONAL PARK
Mammoth Cave, Kentucky /52,830 acres
Skip the too-tame subterranean walking tour. Instead, rent a CANOE and CAST for crappie and black bass on the Class I Green River, 26 miles of which flow through the beech- and hickory-shaded park. Camp on small islands and sandbars along the way.
MESA VERDE NATIONAL PARK
Mesa Verde, Colorado / 52,122 acres
Most tourists stick to the paved walkways. You, of course, hit the dirt. HIKE the rarely traveled Petroglyph Point Trail, a 2.8-mile out-and-back starting at the Spruce Tree House, and you'll stand eye-to-eye with dozens of 900-year-old Anasazi petroglyphs.
MOUNT RAINIER NATIONAL PARK
Ashford, Washington / 235,625 acres
Summit 14,410-foot Rainier via the pristine, little-traveled Tahoma Glacier route on the mountain's southwestern slope. Grade II-III MOUNTAINEERING skills are required; the technically challenged can stop just below 11,000 feet at St. Andrews Rock, from which, on a clear day, you can see Seattle.
NATIONAL PARK OF AMERICAN SAMOA
Pago Pago, American Samoa / 9,000 acres
Camping is not permitted in this lush South Pacific wilderness. But the park's homestay program lets you sleep in a fale, an open-air thatch-roofed hut, with a native Samoan family, who'll teach you to weave palm baskets and fansor just show you the best spots for DIVING and SNORKELING.
NORTH CASCADES NATIONAL PARK
Sedro-Woolley, Washington / 504,781 acres
Your reward for hauling your MOUNTAIN BIKE on the ferry for the 50-mile trip up Lake Chelan to the Purple Point Visitors Center: a stunningly beautiful ride past gorges and glacier-fed waterfalls on the gravel Stehekin Valley Road (23 miles one-way). Stay at one of several primitive campsites along the route.
PETRIFIED FOREST NATIONAL PARK
Petrified Forest, Arizona / 93,533 acres
No trails, no touristsjust you, your backpack, and miles of psychedelic wilderness. The red-, purple-, and white-banded spires and stonelike, sculpted trees in the 45,000-acre Northern Wilderness Area are a six-mile HIKE from the Kachina Point parking lot.
REDWOOD NATIONAL PARK
Crescent City, California / 112,613 acres
There's no gnarly singletrackthis is a national parkbut you'll get off the busy paved hiking trails and see groves of 300-foot-tall, thousand-year-old redwoods when you PEDAL the 11.5-mile Holter Ridge Trail, an old logging road that switchbacks along the park's eastern boundary.
SAGUARO NATIONAL PARK
Tucson, Arizona / 91,445 acres
It's just outside Tucson's urban sprawl, but few city dwellers HIKE the 16.5-mile Tanque Verde Ridge Trail, which rises 5,600 feet from the desert floor (home to 20-foot-tall saguaros) to the cooler, wetter Rincon Mountains.
SEQUOIA AND KINGS CANYON NATIONAL PARKS
Three Rivers, California / 864,411 acres combined
Sign on for a six-day HORSEPACKING trip with Horse Corral Pack Station (from $195 per day; 559-565-3404) and you'll trot through craggy Cloud and Deadman Canyons and camp near the trout-filled Roaring River.
559-565-3135 (Sequoia), 559-565-4307 (Kings Canyon), www.nps.gov/seki
SHENANDOAH NATIONAL PARK
Luray, Virginia / 199,016 acres
Lose the auto-tour crowd at mile 25.3 on Skyline Drive to HIKE a 12-mile loop through rolling hardwood forests on the connecting Thornton River, Hull School, Piney Branch, and Appalachian Trails. Afterward, slurp a wild mountain blackberry shake in nearby Elkwallow.
VOYAGEURS NATIONAL PARK
International Falls, Minnesota / 218,200 acres
Pitch your tent at the primitive Cruiser Lake Campsite, far from the motorboats and floatplanes that plague most of this North Woods park's 30 glacier-carved lakes. Borrow an on-site CANOE, CAST for three-pound lake trout, and listen for loons.
WIND CAVE NATIONAL PARK
Hot Springs, South Dakota / 28,295 acres
Squeeze into ten-inch passages and check out Wind Cave's famous boxworka rare, honeycomb calcite formation that makes geologists giddyon the guided, four-hour Wild Cave Tour. Basic SPELUNKING experience is recommended.
WRANGELL-ST. ELIAS NATIONAL AND PRESERVE
Copper Center, Alaska / 13.2 million acres
See the heart of Wrangell-St. Eliastumbling tidewater glaciers, spruce forests, and jagged coastal mountainson a 13-day, 200-mile RAFT trip on the Class II Copper River in July or August with St. Elias Alpine Guides (from $2,800 per person; 888-933-5427).
ZION NATIONAL PARK
Springdale, Utah / 146,592 acres
Slither through three-foot-wide slot canyons and rappel down 12- to 20-foot ledges in the 12-mile-long Orderville Canyon (accessed from the North Fork Road, outside the park's east entrance). Basic canyoneering skills and neoprene socks are essential.