41,376 campgrounds
Glacier National Park
Haleakala National Park
Hawaii Volcanoes National Park
Zion National Park
Canyonlands National Park
Olympic National Park
Mount Rainier National Park
Isle Royale National Park
Yellowstone National Park
Great Smoky Mountains National Park
Everglades National Park
Great Basin National Park
Death Valley National Park
Mammoth Cave National Park
Saguaro National Park
Crater Lake National Park
