America's Most Underrated National Parks

Ninety-five percent of this colorful park on Miami's doorstep is underwater. Save for 30 islets and a mangrove forest fringe on the mainland, Biscayne is 173,000 acres of Caribbean-clear waters that wash over the sea-grass shallows of Biscayne Bay—and the world's third largest coral reef.

Cool Fact: There are 72 shipwrecks in the park. Six are part of a Maritime Heritage Trail opening in late 2010. The 112-foot schooner Mandalay (a posh windjammer cruiser sunk in 1966) is shallow enough for snorkelers.

Don't Miss: Some of the best snorkeling and scuba diving in the United States. Swim with manatees and more than 200 species of fish—colorful coral-nibblers, toothy silver barracuda, and 500-pound groupers.

Congaree is a slice of the bayou just outside Columbia, SC. Its some 27,000 acres of floodplain (the polite word for "swamp") were set aside to preserve the largest remaining tract of old-growth bottomland hardwood forest in the United States.

Cool Fact: This is serious forest, including some of the tallest trees (the loblolly pines can reach nearly 170 feet) in the eastern United States, forming one of the highest natural canopies in the world.

Don't Miss: Free, ranger-guided weekend canoe tours on Cedar Creek, which flows gently around the knuckles of ancient bald cypress and tupelo garlanded with Spanish moss.

This gorgeous park near Thunder Bay, Canada, is the largest island in the world's largest freshwater body (by surface area), Lake Superior. Though it ranks as the fifth least-visited park (14,000 annual visitors) in the nation, it has the highest backcountry use. It's accessible only by boat or seaplane and is one of the few national parks to close in winter.

Cool Fact: The isolation makes this a unique bio-preserve. Isle Royale has freshwater clams, snails, and insects in sizes and densities not seen elsewhere since the 1800s (bring DEET). It's also the only place where moose and wolves coexist without bears to balance atop the predator pole.

Don't Miss: A boat tour around some of the park's 400 satellite islands, and a backcountry camping trip.

The Gunnison thunders down the steepest mountain descent of any river in the United State s through one of the most spectacular and deepest canyons in the country. The less-trafficked North Rim has a great campground, at the lip of a nearly 2,000-foot plunge into the gorge.

Cool Fact: Stack the Empire State Building atop the Willis Tower (a.k.a. Sears Tower) and you'd still be two stories short of the canyon rim at Warner Point, 2,722 feet above the river.

Don't Miss: Rafting the Gunny itself—a raging river of Class III to IV rapids sluicing though a canyon that's often only 40 feet wide between mighty rock walls rising hundreds of feet—in the adjacent Gunnison Gorge National Conservation Area.

This landscape of mythic western history, where Sitting Bull fought and General Custer hounded the Sioux, has the same eerily eroded badlands, shaggy buffalo, and bighorn sheep that draw crowds to Badlands National Park in South Dakota—but with half the visitors. Also: wild horses.

Cool Fact: In 1883, a 25-year-old politician from back East arrived in these parts to hunt buffalo. He started the first of several ranches (now part of the park) and began his extreme image makeover from scrawny New Yorker to strapping western adventurer (and future president) Teddy Roosevelt.

Don't Miss: A horseback ride through the hills and badlands, splashing across the Little Missouri River.

Capitol Reef was established around a massive, 100-mile-long wrinkle in the earth's crust called the Waterpocket Fold (the "reef" in the park name). This awesome and colorful mountainous layer cake showcases 10,000 feet—and 270 million years—of sedimentary history.

Cool Fact: The most popular day hike—Capitol Gorge, down a twisting dry-wash canyon, past a majestic domelike outcropping, to a series of natural water cisterns—takes you through the hills that were once the hideout of Butch Cassidy and his Wild Bunch.

Don't Miss: The spectacular drive to the park from the west along Route 12, and the 1,400-year-old Indian petroglyphs on the roadside cliffs above the many orchards of Fruita, a historic hamlet where mule deer graze under the shade of cottonwoods along the Fremont River.

This remote desert park in east-central Nevada has plenty of groves of gnarled bristlecone clocking in at more than 4,000 years old, as well as aspen, jackrabbits, and alpine wildflowers spread over 77,000 acres that range from the basin floor at 5,000 feet above sea level to peaks topping 13,000 feet.

Cool Fact: The skies over isolated Great Basin rank among the darkest in the lower 48 states, providing some of the best stargazing in the nation.

Don't Miss: The glittering marble caverns of Lehman Caves, and the 3.4-mile round-trip hike to the Lexington Arch, a rare aboveground limestone arch that, at six stories, is one of the largest in the United States.

Fifty miles from Bellingham on the Canadian border is a picture-postcard Pacific Northwest landscape of sawtooth mountains slung with hammocks of snow. More than 300 glaciers feed some of the country's highest waterfalls, and wildlife, including the occasional grizzly, prowl the park's old-growth forests.

Cool Facts: North Cascades is one of the snowiest places on earth and contains more than half of the glaciers in the lower 48 states. It also has the highest number of recorded plant species of any national park in the country.

Don't Miss: A hike on the nearly 400 miles of trails—perhaps the stiff, 12-mile-round-trip Cascade Pass–Sahale Arm Trail winding through wildflower fields past waterfalls and glaciers with panoramas of some of the park's 127 alpine lakes.

Just offshore from developed SoCal lie the Channel Islands, five of which are protected as a national park. Fewer than 30,000 people actually leave the mainland to explore the islands themselves, where 175 miles of untrammeled shores make pristine breeding grounds for harbor seals and sea lions.

Cool Facts: Among the islands' more than 2,000 plant and animal species are 145 found nowhere else in the world; they also have one of the best-preserved archaeological records on the Pacific coast, documenting 10,000 years of continuous human habitation.

Don't Miss: A boat tour during whale migrations (blue and humpback in summer, gray from late December to mid-March) and a hike on the easy, 1.5-mile Anacapa Loop trail, which runs along the island's dramatic ridgeline.

At 13.2 million acres of Alaskan wilderness, this, the largest U.S. park, is six times the size of Yellowstone and larger than nine U.S. states—yet it has only two roads, together barely totaling 105 miles. Combined with its contiguous neighbor parks, the 24 million acres form the world's largest international protected area, and a UNESCO World Heritage Site.

Cool Facts: The park has North America's highest concentration of glaciers and encompasses nine of the 16 tallest mountains in the U.S. The park's namesake, the 14,163-foot Mount Wrangell, is one of the world's largest active volcanoes; on clear days, you can see it smoking.

Don't Miss: A tour of the historic Kennecott copper mine buildings, followed by lunch at the New Golden Saloon in the funky former boomtown of McCarthy (pop: 42). Or, try rafting the Copper River or world-class fishing in Yakutat.