Among the 63 national parks in the United States, 13 are also World Heritage sites. A few—Grand Canyon, Yellowstone, Yosemite—have the spectacular landscapes, unique biodiversity, and cultural significance to make them clear contenders for the double crown, while others are less obvious choices.
What does it take to be a World Heritage site? According to UNESCO, there are 10 criteria for natural and cultural sites, qualifications full of terms like “outstanding example” and “exceptional natural beauty.” (A site must meet at least one of the criteria.) Read on to discover the baker’s dozen of these elite parks and a few of the reasons they gained their UNESCO distinction.
Sometimes called a “river of grass,” Everglades National Park has an exceptional variety of water habitats.
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Everglades National Park
A World Heritage site since 1979
This Florida park, with its vast subtropical wetlands and coastal ecosystems, has the dubious distinction of being the only one on this list that UNESCO considers endangered. Such issues for a park can include a decline in population of local species, climate change, and encroachment by people. It became a national park in 1947, and UNESCO added it to the endangered list in 2010.
Carlsbad Caverns National Park
A World Heritage site since 1995
With more than 100 caves, this park in New Mexico includes one of the nation’s deepest limestone caves and its largest chamber, the aptly named Big Room. Stalactites and stalagmites continue to form in such places as Lechuguilla Cave, famed for its beauty and its length (over 77 miles). Carlsbad Caverns became a national park in 1930.
Olympic National Park
A World Heritage site since 1981
At the top of Washington State’s Olympic Peninsula, Olympic National Park contains a stellar temperate rain forest, the largest in the Western Hemisphere. The diversity here includes ocean coastline, glaciers, subalpine meadows, and coniferous forests. It became a national park in 1938.
Yellowstone National Park has more than 10,000 geothermal features.
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Yellowstone National Park
A World Heritage site since 1978
Besides its geothermal diversity (more geysers than anywhere else, plus mud pots, fumaroles, and hot springs), this park in Wyoming, which was created in 1872, is a must-see for its wildlife and the Grand Canyon of the Yellowstone River. Grizzly bears, bison, and wolves are among the four-legged attractions.
Mammoth Cave National Park
A World Heritage site since 1981
In addition to being the longest cave system on Earth, stretching several hundred miles, the many caves at this Kentucky park are loaded with plant and animal life. People have been touring the caves since the early 19th century; it became a national park in 1941.
Together with a Canadian national park, Glacier forms Waterton Glacier International Peace Park.
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Glacier National Park
A World Heritage site since 1995
This national park is not only also a World Heritage site but also an International Peace Park, 1 of 47 U.S. Biosphere Reserves, and an International Dark Sky Park. (It’s the only place in the nation with all five designations.) The Montana park became the world’s first International Peace Park when it combined in 1932 with Waterton Lakes national park in Alberta, Canada. The status recognizes the goodwill between the United States and Canada, which share the world’s longest undefended border. In addition to its namesake—rapidly shrinking glaciers—the park is home to cougars, grizzly bears, and wolverines.
Redwood National Park
A World Heritage site since 1980
This California state and national park contains the world’s biggest coastal redwood forest, with some of the planet’s oldest and tallest trees. With 200 miles of hiking trails, it’s perfect for getting away from it all: There are no hordes of visitors here, and there are no lodges but ample options for camping.
Mesa Verde National Park
A World Heritage site since 1978
Of the 13 parks in this category, Mesa Verde is the only one that UNESCO classifies as “cultural” rather than “nature” due to the Ancestral Puebloan people who lived in these cliff dwellings for hundreds of years. When this national park was established in Colorado in 1906, it was the globe’s first archaeology site to obtain a protected status.
Hawaii Volcanoes National Park contains two of the world’s most active and best understood volcanoes, Kilauea, pictured here, and Mauna Loa.
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Hawaii Volcanoes National Park
A World Heritage site since 1987
For Native Hawaiians, Volcanoes National Park is known as the land where the gods dwell, in particular Pele (goddess of fire), who lives in the Halemaumau crater atop Kilauea, one of two active volcanoes here. The other, Mauna Loa, when measured from the ocean floor, is the largest volcano on the planet: an apt measurement, for these volcanoes are prime examples of island builders. The park, on the Big Island, features forests of huge ferns, the Ka’u Desert, steam vents, and black lava galore.
Great Smoky Mountains National Park
A World Heritage site since 1983
OK, maybe having the world’s largest variety of salamanders isn’t the main draw to this popular park in Tennessee and North Carolina, but their presence indicates that much of this land is undisturbed by people. A true nature refuge, and a national park since 1934, Great Smoky Mountains also features nearly as many different species of trees as there are in all of Europe.
Glacier Bay and its neighbor parks contain some of the world’s longest and most spectacular glaciers.
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Glacier Bay National Park
A World Heritage site since 1979
This Alaskan park, created in 1980, is on the U.S./Canadian border and meets three other national parks: Wrangell–St. Elias, Kluane, and Tatshenshini-Alsek. Although these parks are individually managed (the last two are Canadian), they work together to follow similar guidelines related to resource management, visitor use and interpretation, and more. Here you’ll find the globe’s largest nonpolar icefield as well as the namesake glaciers, plus sizable populations of Dall sheep, caribou, and grizzly bears.
Grand Canyon National Park
A World Heritage site since 1979
At nearly a mile deep, this epic gorge in Arizona carves through 275 miles and was formed over 6 million years by the Colorado River. Its width varies from a third of a mile to over 18 miles. It became a national park in 1919.
Yosemite National Park
A World Heritage site since 1984
Erosion by glaciers over millions of years created the dramatic landscapes of this park, located in California’s Sierra Nevada and was first protected in 1864. (It became a national park in 1890.) Alpine meadows and lakes, groves of giant sequoia trees, and five of the Earth’s highest waterfalls are among the features here.
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