When were the national parks set up?

The first national park, Yellowstone National Park, was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872. Since then, the National Park System has grown to include over 400 areas that are managed by the National Park Service (NPS). These areas include national parks, national monuments, national historic sites, national military parks, national battlefields, national seashores, national recreation areas, national preserves, and national parkways.