See America's Top 10 Natural Wonders

En español | The Yellowstone Caldera is the beating heart of a supervolcano. It's also the hot spot that fuels all of the amazing thermal features in Yellowstone National Park, including geysers, such as Old Faithful, and the numerous hot springs, gurgling mud pots and steaming fumaroles.

This is one of the most beautiful places on earth. The panorama includes El Capitan, the world's largest monolith of exposed granite; the distinctive Half Dome granite formation; and Yosemite Falls, the tallest waterfall in North America, measuring 2,425 feet from top to bottom.

Of all the stunning geology in the southern reaches of Utah, Bryce Canyon stands out. The distinctive and otherworldly sandstone formations known as hoodoos that populate the valley floor were once arches that slowly lost their tops to the erosive forces of water and air.

In wet season, Florida's southern tip essentially becomes a massive, slow-moving river that's roughly 60 miles wide and 100 miles long. The wildlife that call this swamp home include alligators, panthers, armadillos and manatees.

The tallest mountain in North America, Denali (aka Mount McKinley) looms above 6 million acres of national park and preserve. Grizzly bears and other wildlife are rife on both the low-elevation taiga and the alpine tundra.

The lowest and hottest place in North America, Death Valley bottoms out at Badwater Basin (282 feet below sea level) and has topped out at 134 degrees Fahrenheit. But it's not all scorching desert: Telescope Peak (11,043 feet) towers over the valley floor.

Rising from the sage-studded floor of the San Luis Valley in southern Colorado are the tallest sand dunes in North America. The aptly named 650-foot High Dune offers persevering hikers an amazing view into the heart of the dune field, an amazing byproduct of water, wind and time.

The only subterranean spot on our list of top 10 natural wonders, Mammoth Cave is the largest known cave system on the planet. The natural labyrinth consists of nearly 400 explored miles of serpentine tunnels.

The most iconic mountains in the West rise 6,000-plus feet above the floor of Jackson Hole, home to the meandering Snake River and unforgettable vistas around every bend. South of Grand Teton National Park is the world-class skiing mecca Jackson Hole Mountain Resort.

This rugged, wild coastline is home to the world's tallest trees: the coast redwoods, which can top out at 350 feet or more. The location of the tallest one, the 379-foot Hyperion, is a closely guarded secret to keep crowds away.

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