Before the arrival of European settlers, the only residents on the plateau were small bands of Shoshone Indians known as “Sheepeaters,” who lived on the southern fringe. Three other Native American tribes came and went: the Crows (Apsáalooke), who were friendly to the settlers; the Blackfeet, who lived in the Missouri Valley drainage and were hostile to both Europeans and other tribes; and the Bannocks, who largely kept to themselves. The nomadic Bannocks traveled an east-west route in their search for bison: from Idaho past Mammoth Hot Springs to Tower Fall, and then across the Lamar Valley to the Bighorn Valley, outside the park’s current boundaries. Called the Bannock Trail, the route was so deeply furrowed that evidence of it still exists today on the Blacktail Plateau near the Tower Junction.

The first explorer of European descent to lay eyes on Yellowstone’s geothermal wonders was probably John Colter, who broke away from the Lewis and Clark expedition in 1806 and spent 3 years wandering a surreal landscape of mud pots, mountains, and geysers. When he described his discovery on his return to St. Louis, no one believed him. Miners and fur trappers followed in his footsteps, reducing the plentiful beaver population of the region to almost zero, and occasionally making curious reports of a sulfurous world still sometimes called “Colter’s Hell.”

The first significant exploration of what would become the park took place in 1869, when a band of Montanans, led by David Folsom, completed a 36-day expedition. The group traveled up the Missouri River and into the heart of the park, where they discovered the falls of Yellowstone, mud pots, Yellowstone Lake, and the Fountain Geyser. Two years later, an expedition led by U.S. Geological Survey director Ferdinand V. Hayden brought back convincing evidence of Yellowstone’s wonders, in the form of astonishing photographs by William Henry Jackson.

A debate began over the potential for commercial development and exploitation of the region, as crude health spas and thin-walled “hotels” went up near the hot springs. There are various claimants to the idea of a national park—members of the Folsom party later told an oft-disputed story about thinking it up around a campfire in the Upper Geyser Basin—but the idea gained steam as Yellowstone explorers hit the lecture circuit back East. In March 1872, President Ulysses S. Grant signed legislation declaring Yellowstone the nation’s first national park.

The Department of the Interior got the job of managing the new park. There was no budget for it and no clear idea of how to take care of a wilderness preserve; many mistakes were made. Inept superintendents granted favorable leases to friends with commercial interests in the tourism industry. Poachers ran amok, and the wildlife population was decimated. A laundry business near Mammoth went so far as to clean linens in a hot pool.

By 1886, things were so bad that the U.S. Army took control of Yellowstone; iron-fisted management practices resulted in new order and protected the park from those intent on exploiting it. (However, the military did participate in the eradication of the plateau’s wolf population.) By 1916, efforts to make the park more visitor-friendly had begun to show results: Construction of the first roads had been completed, guest housing was available in the area, and order had been restored. Stewardship of the park was then transferred to the newly created National Park Service, which remains in control to this day.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.