Yellowstone National Park was established as the United States’ first national park on March 1, 1872.
President Ulysses S. Grant signed the Yellowstone National Park Protection Act on that date. The law set aside a vast region centered mainly in present-day Wyoming, with small portions in Montana and Idaho. It described the land as a public park for the benefit and enjoyment of the people.
Yellowstone’s geothermal features, including geysers, hot springs, and mud pots, helped inspire support for preservation. The 1871 Hayden Geological Survey produced reports, maps, photographs, and paintings that brought the region’s landscape to wider public attention. Native peoples had lived in and traveled through the region for thousands of years before the park was created.
Yellowstone is widely described as the world’s first national park, although earlier countries had protected particular forests, landscapes, or hunting grounds. The National Park Service was not created until 1916; the U.S. Army managed Yellowstone for much of the period before then.