University of Montana archaeologists have been excavating in Yellowstone National Park and have come to the conclusion that the area was a popular summer camp long before modern day Americans came to enjoy the natural geological features.
     Evidence has been found to suggest that the area around the Yellowstone Lake was hunted by Native Americans from all parts of the northwest of the North American continent. The area is also rich in deposits of Obsidian which was used to make tools and weapons.
     A 5,800 year old hearth has been found, together with a 3,000 year old volcanic boulder table. The obsidian artefacts found indicate that there was a north/south divide around the lake, with spear points and arrow heads manufactured on the north shore being traded north, west & east of the area whilst south shore traders stayed their side of the lake.

Source: Missoulian (3 April 2010)