In Pictures: Yellowstone National Park
In Pictures: America's National Parks
In Pictures: Mountain climbers
In Pictures: Alaska, all natural
In Pictures: Sticky mess: The Gulf oil spill's impact on nature
In Pictures: Rare and Beautiful Natural Phenomena
Delicate Arch glows in light from the setting sun as alpenglow illuminates the La Sal Mountains in the distance at Arches National Park near Moab, Utah. Julie Jacobson/AP/File
Snow covers redwood trees in Sequoia National Park, California. Joe Sohm/Newscom/File
Tourists stand at Mathers Point as snow blankets the upper rim of the Grand Canyon in Arizona. Rob Schumacher/The Arizona Republic/AP/File
Bison graze in Yellowstone National Park near Gardiner, Mont. Ted S. Warren/AP/File
Hoarfrost encrusts Joshua trees in Death Valley National Park, California. DanitaDelimont.com/Newscom/File
Fresh snow covers the badlands in Theodore Roosevelt National Park in North Dakota. Chuck Haney/Newscom/File
Yosemite National Park makes a striking winter scene in California. Zumapress.com/Newscom/File
A dusting of snow brings out the architectural forms of Mesa Verde National Park in Colorado. Lonely Planet Images/Newscom/File
Sparkling snow and a brilliant blue sky set off the red rocks in Bryce Canyon National Park, Utah. DanitaDelimont.com/Newscom/File
New snow covers the canyon walls near the Virgin River in Zion National Park, Utah. DanitaDelimont.com/Newscom/File
The sharp peaks of Grand Tetons National Park are softened by a blanket of snow. Newscom/File
In Pictures: Derby Day devotees, Kenyan style
Photos of the Day: Photos of the day 05/16
In Pictures: Dazzle like Beckham
In Pictures: Weather extremes 2013
Photos of the Day: Photos of the day 05/15
In Pictures: Duchess Kate's royal baby bump
Photos of the Day: Photos of the day 05/14
In Pictures: Keffiyeh is rebel chic
Will Stauffer-Norris and Zak Podmore traveled 1,700 miles to assess the state of the beautiful but threatened Colorado River.
The schedule: Get up at first light. Wait for the sleeping bags to dry out from the dew. Paddle or float down the Colorado River until dark. Try to find a beach on which to camp out – not always an easy task, with some of the land along the river being privately owned. Read and write at night. Go to sleep and start over again the next day.
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