The National Park Service was established by Congress on August 25, 1916. The duties of the NPS are preserving the National Parks and other areas under their jurisdiction, while also making them accessible for public use.
On August 25, 1916, President Woodrow Wilson signed the bill that directed the agency “to conserve the scenery and the natural and historic objects and wildlife therein, and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.” Stephen Mather was the first director of the NPS. Some of the National Parks existed before the agency, but they were each administered individually under the Department of the Interior. Creation of the NPS put them all under one umbrella.
Two of our best-known National Parks are Yellowstone, established in 1872 by Congress and President Ulysses S. Grant, and Yosemite, officially established as a park in 1890, although Abraham Lincoln signed the Yosemite Grant that protected the Yosemite Valley from development in 1864. It was John Muir who led the a movement to expand the area of protection, taking in the mountains and forests surrounding the valley, as a national park. His efforts, and those of Stephen Mather, eventually led to the NPS.
The Park Service oversees 417 “Units”. Of those, 60 are national parks, located in 28 states and two territories. California has the most (nine).