Yellowstone National Park is a national park of the United States located mainly in the northwest corner of the state of Wyoming, with small portions extending into Montana and Idaho. The park is known for its wildlife and its many geothermal features, especially the Old Faithful geyser, one of its most popular. While it represents many types of biomes, subalpine forest is the most abundant. It is part of the South Central Rockies forests ecoregion.
Native Americans have lived in the Yellowstone region for at least 11,000 years. While non-native mountain men visited during the early-to-mid-19th century, organized exploration by non-natives did not begin until the late 1860s. The park was established by the 42nd U.S. Congress through the Yellowstone National Park Protection Act and signed into law by President Ulysses S. Grant on March 1, 1872. Yellowstone was the first national park in the US, and is also widely understood to be the first national park in the world.
Management and control of the park originally fell under the jurisdiction of the U.S. Department of the Interior, the first Secretary of the Interior to supervise the park being Columbus Delano. However, the U.S. Army was eventually commissioned to oversee the management of Yellowstone for 30 years between 1886 and 1916. In 1917, the administration of the park was transferred to the National Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural and historical significance, and researchers have examined more than one thousand indigenous archaeological sites.
Yellowstone National Park spans an area of 3,468.4 sq mi (8,983 km2), with a large variety of lakes and ponds, canyons, rivers, and mountain ranges. Yellowstone Lake is one of the largest high-elevation lakes in North America and covers part of the Yellowstone Caldera, the largest super volcano on the continent. The caldera is considered a dormant volcano. It has erupted with tremendous force twice in the last two million years. Well over half of the world's geysers and hydrothermal features are in Yellowstone, fueled by this ongoing volcanism. Lava flows and rocks from volcanic eruptions cover most of the land area of Yellowstone. The park is the centerpiece of the Greater Yellowstone Ecosystem, the largest remaining nearly intact ecosystem in the Earth's northern temperate zone. In 1978, Yellowstone was named a UNESCO World Heritage Site.
Hundreds of species of mammals, birds, fish, reptiles, and amphibians have been documented, including several that are either endangered or threatened. The vast forests and grasslands also include unique species of plants. Yellowstone Park is the largest and most famous megafauna location in the contiguous United States. The park is inhabited by grizzly bears, cougars, wolves, and free-ranging herds of bison and elk. The Yellowstone Park bison herd is the oldest and largest public bison herd in the United States. Forest fires occur in the park each year; in the large forest fires of 1988, over one-third of the park was burnt. Yellowstone has numerous recreational opportunities, including hiking, camping, boating, fishing, and sightseeing. Paved roads provide close access to the major geothermal areas as well as some of the lakes and waterfalls. During the winter, visitors often access the park by way of guided tours that use either snow coaches or snowmobiles in the snowy weather.
The Yellowstone area is known by many names in surviving Native American languages, for instance pashaka ("white mountain country") in Assiniboine, aw' pawishe ("land of steam") in Crow, and memut neespah ("boiling earth") in Nez Perce. The English name "Yellowstone" derives from the Hidatsa term for the Yellowstone River, miʔcíiriaashish, which was translated as "Yellow Stone" in 1797 during the expedition of Canadian explorer David Thompson.
The archaeological record shows continuous use of the Yellowstone region by Native Americans from the earliest era of human presence in the Americas (the Lithic stage, prior to 8500 BC) through to the national park's founding. During the construction of the post office in Gardiner, Montana, in the 1950s, an obsidian point of Clovis origin was found that dated from approximately 11,000 years ago. The earliest consistent visits to Yellowstone are linked to the Cody complex circa 7300 BC. The Mummy Cave site indicates that the Cody complex followed migrating bison herds to Yellowstone and regularly mined obsidian from Obsidian Cliff. Excavations within the park show that Cody people camped on the eastern side of Yellowstone Lake during the summers, fishing and boating on the lake and hunting bear, deer, and bison.
Use of Obsidian Cliff peaked in the Late Prehistoric period (1000 BC–1000 AD). Thousands of pounds of obsidian was transported thousands of miles to Ohio using the Missouri, Mississippi, and Ohio rivers between roughly 200 BC–400 AD for use as ceremonial goods by the Hopewell Culture. Hopewell grave goods include not only obsidian, but also copper shaped to resemble the horns of bighorn sheep native to the Rockies, which suggests the Hopewell may have visited Yellowstone themselves.
More recently, around 500–1000 AD, the Shoshone summered on the southern end of Yellowstone Lake. It is likely that regular visits to Yellowstone by the Crow, Nez Perce, Blackfoot, and Salish peoples also began in the pre-Columbian era, although archaeological findings are lacking. In oral traditions, the Shoshone, Blackfoot, and Salish recall women gathering cinnabar and other resources at Obsidian Cliff and making prayers there. Pre-Columbian peoples managed Yellowstone's forest ecosystem using low-intensity fires. They were aware that fire produced green grass which would attract bison.
Late Native use and Western exploration
The arrival of European horses, followed eventually by mountain men and fur traders in the Rocky Mountains, slowly began to impact the Yellowstone region in the mid-nineteenth century. The Shoshone were the first Rocky Mountain tribe to obtain horses in the early 1700s, but the Shoshone tribe which lived within Yellowstone, the Tukudeka (Sheepeaters), did not make use of horses, instead tracking bighorn sheep on foot. From the 1840s, the Bannock people (Kutsutɨkaˀa) regularly rode from their home territory near Henrys Lake through Mammoth Hot Springs and along what is now the northern stretch of the Grand Loop Road on the way to buffalo hunts in the Bighorn Mountains, in the lands of the Crow people (Apsáalooke). This route, called the Great Bannock Trail by park rangers, allowed the Bannock to regularly fraternize with the Crow, their allies against the Blackfoot Confederacy (Niitsítapi).
The first written report of unusual features at Yellowstone came in the form of second-hand accounts mentioned in a letter written to James Wilkinson in September 1805. In winter of 1807–1808, John Colter, who had earlier been a member of the Lewis and Clark Expedition, passed through what later became the northeast corner of the park, near Tower Fall. He described a particularly active geothermal site outside of the present-day park as "hell" due to its sulphuric smell, and Washington Irving later dubbed it "Colter's Hell," a name that has stuck. Colter is the first American citizen known to have entered the park, although his exact route is hotly contested. Over the next 40 years, numerous reports from mountain men and trappers such as Jim Bridger told of boiling mud, steaming rivers, and petrified trees, but these were considered little more than dubious rumors. By 1863, there was some understanding of the region's basic geography and natural features but still no detailed, written account.
In spring 1864, a group of Piegan Blackfeet led the Belgian Jesuit Xavier Kuppens on a tour of the geysers and other major attractions, which they were familiar with. In 1865, Kuppens shared details of what he saw with regional political leaders including Montana Territory Governor Thomas Francis Meagher, who may have suggested preserving the region as a national park, although this conversation was only recalled decades later. From 1866–68, local curiosity about the Yellowstone region was interrupted by Red Cloud's War.