
The most popular national park: The most popular of the National Park Service's 59 headliner National Parks in 2016, Great Smoky Mountains National Park attracted more than 11 million visits in its centennial year. The park, which straddles the North Carolina/Tennessee border, has incredible views, like this one at sunrise of the Oconaluftee Valley.

2. Grand Canyon National Park, Arizona: The Grand Canyon is 277 river miles long, up to 18 miles wide in parts, and a mile deep. Mather Point along the park's South Rim is a spectacular place from which to view the sunset.

3. Yosemite National Park, California: President Abraham Lincoln signed legislation in 1864 protecting a portion of what is now Yosemite National Park. It was the first instance of the US government setting aside scenic wilderness for public use and preservation. Cook's Meadow and Yosemite Falls are shown here.

4. Rocky Mountain National Park, Colorado: This 415-square-mile park's elevation ranges from 7,600 feet to 14,259 feet, and the park is home to 77 peaks above 12,000 feet. The park, which hosts a diversity of animal and plant life, also straddles the Continental Divide. Dream Lake is shown here.

5. Zion National Park, Utah: Zion is the most popular of Utah's "Mighty Five" national parks, which include Arches, Bryce Canyon, Canyonlands and Capital Reef. The Zion hike to Angels Landing is hard but worth it; from there, hikers get views of the whole canyon.

6. Yellowstone National Park, Idaho/Montana/Wyoming: The world's first National Park, Yellowstone is one of the last large ecosystems on the planet's northern temperate zone. It's home to more than 300 geysers, a volcano and many waterfalls. It's also home to the few remaining members of a wild, continuously free-ranging bison herd that once roamed the Great Plains.

7. Olympic National Park, Washington: Olympic has everything an outdoors lover could ask for: over 70 miles of untamed coastline, old-growth temperate rain forests, glacier-capped mountains and this incredible view from a ridge at Deer Park.

8. Acadia National Park, Maine: The first National Park east of the Mississippi, Acadia is the most eastern park and therefore the first US National Park to welcome the sunrise.

9. Grand Teton National Park, Wyoming: The Teton Range at this national park rises 7,000 feet above the valley at Jackson Hole. The 13,770-foot-tall Grand Teton is the highest peak, but there are eight peaks more than 12,000 feet in elevation.

10. Glacier National Park, Montana: The glaciers for which this national park is named are disappearing. In 1850, there were an estimated 150 glaciers in the area now within the park's boundaries. Now there are 25, many of which are smaller versions of themselves. They may all be gone by 2030.