Which national park became the world's first national park in 1872, part of the United States story remembered by America250?

Yellowstone National Park became the world's first national park in 1872.

President Ulysses S. Grant signed the Yellowstone National Park Protection Act on March 1, 1872. The law reserved the region around Yellowstone's geothermal features, lakes, and landscapes “for the benefit and enjoyment of the people.” It established a federal model for protecting a large natural area from private settlement and commercial exploitation.

Yellowstone lies primarily in northwestern Wyoming, with portions extending into Montana and Idaho. Its features include Old Faithful, the Grand Prismatic Spring, Yellowstone Lake, and the Grand Canyon of the Yellowstone. The park sits above a large volcanic system that helps power its geysers and hot springs.

Yellowstone is often described as the first national park in the world, not merely the first in the United States. Yosemite became a national park in 1890, Sequoia in 1890, and Grand Canyon in 1919. The national-park idea later spread internationally.