The National Park Service turns 101 on Aug. 25, 2017. It’s also one of the 10 days this year that all National Park Service sites (more than 400 parks across the country) offer free admission to everyone. 

Other upcoming free admission days are Saturday, Sept. 30 (National Public Lands Day) and Veterans Day weekend, Nov. 11-12.

Arizona sites include the Grand Canyon, Lake Mead, Canyon de Chelly, Saguaro National Park near Tucson, Montezuma Castle in Camp Verde and many more.

Any fourth grade student can also get a free annual National Parks pass through the Every Kid in a Park program, and active duty military and citizens with a permanent disability can also get free passes.