States marked their first steps toward creating state parks when California accepted control of Yosemite Valley and the Mariposa Grove of Big Trees in a transfer from President Abraham Lincoln in 1864. Lincoln made clear the state must ensure both preservation and access. While Yosemite was eventually ceded back to the federal government so it could serve as a national park, other states soon established their own parks. New York created the Niagara Reservation in 1885 to protect its waterfalls from commercialization, and Pennsylvania created Valley Forge State Park in 1893 to preserve its historical significance.
State parks grew during the Great Depression when the Civilian Conservation Corps employed citizens to plant billions of trees, build trails, campgrounds and lodges. Today there are 2,879 state parks, and the state that started it all has also added the most recent—Dos Rios State Park in California. Source: Locate a state park