15,000 years ago, glaciers and a continental ice sheet covered most of what is now Yellowstone National Park. They left behind rivers and valleys people could follow in pursuit of Ice Age mammals such as the mammoth and the giant bison. The last period of ice coverage ended 13,000–14,000 years ago, and sometime after that and before 11,000 years ago, humans arrived here.

Evidence of these people in Yellowstone remained un-investigated, even long after archeologists began excavating sites elsewhere in North America. Archeologists used to think high regions such as Yellowstone were inhospitable to humans and thus, did little exploratory work in these areas. More than 1,800 archeological sites have been documented in Yellowstone National Park, which contain evidence of successful hunts for bison, sheep, elk, deer, bear, cats, and wolves.

Some of the historic peoples from this area, such as the Crow and Sioux, arrived sometime during the 1500s and around 1700, respectively. We have little scientific evidence to conclusively connect other historic people, such as the Salish and Shoshone, to prehistoric tribes, but oral histories provide links. Prehistoric vessels known as “Intermountain Ware” have been found in the park and surrounding area, and link the Shoshone to the area as early as approximately 700 years ago.

One of the surviving Native American trails, the Bannock Trail, was once used to access the buffalo plains east of the park from the Snake River plains in Idaho, was extensively used from approximately 1840 to 1876. A lengthy portion of the trail extends through the Tower District from the Blacktail Plateau to where it crosses the Yellowstone River at the Bannock Ford upstream from Tower Creek. From the river, the trail's main fork ascends the Lamar River splitting at Soda Butte Creek. Traces of the trail can still be plainly seen in various locations, particularly on the Blacktail Plateau and at the Lamar-Soda Butte confluence.

Credits and Sources:

“Tower-Roosevelt Area Historic Highlights,” National Park Service, http://www.nps.gov/yell/planyourvisit/htower.htm (accessed 1 June 2015).

“The Earliest Humans in Yellowstone,” National Park Service, http://www.nps.gov/yell/learn/historyculture/earliest-humans.htm(accessed 1 June 2015).