Celebrate National Public Lands Day with free admission tomorrow (9/24/16).
There are more 400 national parks to visit with entrance fees ranging from free to $30. The best time to visit the 124 national parks that normally charge an entrance fee is during fee-free days.
Glen Canyon National Recreation Area
Grand Canyon National Park
Lake Mead National Recreation Area
Montezuma Castle National Monument
Organ Pipe Cactus National Monument
Petrified Forest National Park
Pipe Spring National Monument
Saguaro National Park
Sunset Crater Volcano National Monument
Tonto National Monument
Tumacácori National Historical Park
Tuzigoot National Monument
Walnut Canyon National Monument
Wupatki National Monument