Sunflowers growing on sand dunes. (Dunes014)
Greater sandhill cranes leave night roost as sun rises through fog. Monte Vista National Wildlife Refuge, San Luis Valley, Colorado. (Dunes011)
Ducks taking off at sunrise. (Waterfowl141)
Sunrise over Great Sand Dunes National Park, San Luis Valley. (Dunes012)
Great Sand Dunes National Monument. (Dunes151)
Great Sand Dunes National Monument. (Dunes168)
Windswept sand of Killpecker Dunes in Wyoming's Red Desert. (RedDesert011)
Great Sand Dunes National Monument. (Dunes135)
Great Sand Dunes National Monument. (Dunes152)
Great Sand Dunes National Park. (Dunes128)
Great Sand Dunes National Park. (Scenic096)
Great Sand Dunes National Park. (Dunes131)
Great Sand Dunes National Park. (Dunes127)
Cumulus clouds. (080725-00292)
Great Sand Dunes National Park. (Dunes129)
Dunes and reflection. (Scenic360)
Coyote tracks and prairie sunflower at Great Sand Dunes National Park, San Luis Valley, Colorado. (Dunes080)
Fall aspen leaves float on top of a calm pool of water. San Luis Valley, Colorado. (Scenic187)
Sunset and prairie sunflowers (Helianthus petiolaris), Great Sand Dunes National Park. (Dunes007)
Lenticular clouds over Devil's Head. (120115-6089)
Water flowing through Great Sand Dunes National Monument. (Dunes159)
Autumn branches. (Dunes114)
Abstract sunset reflection in water. Alaska. (140902-6425)
Blowing sand, Great Sand Dunes National Park, San Luis Valley. (Dunes030)
People hiking in Great Sand Dunes National Park, San Luis Valley, Colorado. (Dunes032)
Prairie sunflowers (Helianthus petiolaris) growing at Great Sand Dunes National Monument. (Dunes160)
American coots landing in water. (WaterFowl049)
Aerial of Cotton Lake. Dry wetland on Medano Ranch, Great Sand Dunes National Park, San Luis Valley. (Dunes092)
Abstract sunset reflection. Alaska (150803-1170965)
Great Sand Dunes National Monument. (Dunes125)
Wheeler geologic area is formed by erosion of volcanic tuff and ash. San Juan Mountains at the edge of the San Luis Valley. (Dunes025)
Great Sand Dunes National Monument. (Dunes164)
Great Sand Dunes National Park. (Dunes126)