While this type of national park had been proposed previously, the United States established the first "public park or pleasuring-ground for the benefit and enjoyment of the people", Yellowstone National Park, in 1872. Although Yellowstone was not officially termed a "national park" in its establishing law, it was always termed such in practice and is widely held to be the first and oldest national park in the world. However, established by the Mongolian government in 1778, the area surrounding Bogd Khan Uul Mountain located south of the country’s capital, Ulaanbaatar, is probably the oldest national park, predating Yellowstone by nearly a century. The first area to use "national park" in its creation legislation was the U.S.'s Mackinac, in 1875. Australia's Royal National Park, established in 1879, was the world's third official national park. In 1895 ownership of Mackinac National Park was transferred to the State of Michigan as a state park and national park status was consequently lost. As a result, Australia's Royal National Park is by some considerations the second oldest national park now in existence. Canada established Parks Canada in 1911, becoming the world's first national service dedicated to protecting and presenting natural and historical treasures.
The largest national park in the world meeting the IUCN definition is the Northeast Greenland National Park, which was established in 1974. According to the IUCN, 6,555 national parks worldwide met its criteria in 2006. IUCN is still discussing the parameters of defining a national park.
National parks are almost always open to visitors. Most national parks provide outdoor recreation and camping opportunities as well as classes designed to educate the public on the importance of conservation and the natural wonders of the land in which the national park is located.
In 1971, these criteria were further expanded upon leading to more clear and defined benchmarks to evaluate a national park. These include: