Photograph by Panoramic Stock Images
Some 12 million tourists come every year to see the mighty Niagara Falls. Located on the Niagara River on the border between New York and Ontario, Canada, this famed cataract comprises three separate falls: Horseshoe, American, and Bridal Veil.
Photograph by Michael Nichols
A bend in the Colorado River horseshoes around a sandstone butte in Grand Canyon National Park. President Theodore Roosevelt called the canyon—one of the seven natural wonders of the world—"the one great sight every American ... should see." More than four million people do so every year.
Acadia National Park
Photograph by Tim Fitzharris/Minden Pictures
Thunder Hole is a must-see in Maine's Acadia National Park. The feature gets its name from the roar created when waves rush into a narrow slot in the rocks, forcing compressed air out with a boom.
Biker and Glacier
Photograph by Bill Hatcher
A mountain biker makes his way over Black Rapids Glacier in the Alaska Range. Running across the middle of Denali National Park, this range is home to 20,320-foot (6,194-meter) Mount McKinley, North America's highest peak.
Shi Shi Beach
Photograph by Melissa Farlow
The 73 miles (118 kilometers) of coastline protected by Washington's Olympic National Park is speckled with sea stacks like these on Shi Shi Beach. This remote beach is famed for the tidal pools that collect amid the stacks and harbor unparalleled sea life.
Photograph by Pete Ryan
The nearly 600 stone-and-mortar cliff houses notched by the ancient Anasazi into precipitous canyon walls are the most compelling feature of Colorado's Mesa Verde National Park. Cliff Palace, shown here, is the largest, with 151 rooms and 23 circular underground chambers called kivas.
Photograph by Kenneth Garrett
An aerial photo captures the expanse of the National Mall in Washington, D.C., home to the capital city's most important memorials, monuments, and museums. This image shows the Lincoln Memorial (foreground), the Reflecting Pool, the Washington Monument, and, in the distance, the Capitol Building.
Bridalveil Fall, California
Photograph by David Alan Harvey
A shimmering afternoon rainbow frequently fences Bridalveil Fall in Yosemite National Park. The picturesque, 620-foot (190-meter) waterfall is one of many attractions at the California park, which draws more than 3.5 million visitors each year.
Photograph by Walter Meayers Edwards
Arching 275 feet (84 meters) across and 290 feet (88 meters) above the creek bed below, Rainbow Bridge in the Utah desert has been a source of inspiration and wonderment for millennia. Among the largest of all known natural bridges, the sandstone span attracts some 300,000 visitors each year.
Photograph by Raymond Gehman
Tourists look on as Old Faithful, Yellowstone National Park's most famous geyser, sends a tower of scaling water skyward. Recent research suggests the clockwork geyser eruptions are slowing down—and may even stop—due to global warming-related dry spells.
2015 Traveler Photo Contest
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