An ice cave in Wisconsin’s Apostle Island National Lakeshore Park.
Arapaho National Wildlife Refuge in Colorado
Conway Summit Mountain Pass, near Yosemite National Park
Crater Lake National Park
Alaska’s Denali National Park
The Northern Lights above Denali National Park
Alaska’s Glacier Bay National Park
Grand Canyon National Park
Grand Teton National Park
Smoky Mountain National Park
The last light of the day turns the sky pink over Mount Rainier National Park in Washington. Pictured here are the Tatoosh Range and Mount Adams at sunset as seen from the park’s Skyline Trail. Photo by Justin Marx. Tweeted by the US Department of the Interior, 12/7/14.