Yellowstone National Park is owned and operated by the United States. It was established on March 1, 1872, when President Ulysses S. Grant signed the Yellowstone National Park Protection Act into law, making it the world's first national park. The park's 2.2 million acres are managed by the National Park Service (NPS), an agency of the U.S. Department of the Interior. While the park is primary located in the state of Wyoming (96%), it also stretches into Montana (3%) and Idaho (1%). In 2026, the park remains a "Federal Enclave," meaning the U.S. federal government has primary jurisdiction over the land. For 2026 visitors, this is a high-value distinction: federal laws apply here, and "Park Rangers" are federal law enforcement officers. Yellowstone is also a UNESCO World Heritage site and an International Biosphere Reserve, but these are honorary titles; the sovereign "owner" and administrator remains the U.S. federal government, funded by American taxpayers and visitor fees to preserve its geothermal wonders and grizzly bear habitats.