Which national park became the first in the United States when Congress created it in 1872?

Yellowstone National Park became the first national park in the United States when Congress created it in 1872.

President Ulysses S. Grant signed the Yellowstone National Park Protection Act on March 1, 1872. The law reserved more than two million acres around Yellowstone’s geothermal features, lakes, waterfalls, and wildlife, declaring the area a public park for the benefit and enjoyment of the people.

Exploring expeditions and illustrated reports helped persuade lawmakers that Yellowstone’s extraordinary landscape should be protected rather than sold or privately developed. The park is famous for Old Faithful, the Grand Canyon of the Yellowstone, and one of the world’s largest active volcanic systems.

The park’s creation is often described as the beginning of the national-park idea, but Indigenous peoples had long lived in and used the region. Several tribes maintain historical and cultural connections to Yellowstone. The park spans Wyoming, Montana, and Idaho, with most of its area in Wyoming.