Yellowstone National Park was established on March 1, 1872, as the world’s first national park.
President Ulysses S. Grant signed the Yellowstone National Park Protection Act after Congress approved it. The law set aside a large area around the Yellowstone River’s headwaters as a public park, intended for the benefit and enjoyment of the people.
A government-sponsored expedition led by geologist Ferdinand V. Hayden helped persuade Congress to protect the region. The expedition’s reports, photographs by William Henry Jackson, and paintings by Thomas Moran publicized Yellowstone’s geysers, waterfalls, and other geothermal features.
Yellowstone is mainly in Wyoming, with smaller sections in Montana and Idaho. It was initially difficult to administer, and the U.S. Army managed the park from 1886 until the National Park Service took over in 1917. Native peoples had used the region for thousands of years before its national-park designation.