People have lived in the Yellowstone area for about 11,000 years. Some native Americans still lived there when the first people came from Europe in 1807/1808. John Colter, a trapper, came within the Lewis and Clark Expedition and visited a large area that was unknown to the western world at that time. Three years later, he returned to St. Louis and told the people there that he had discovered a wonderland of hot springs and geysers. This area was Yellowstone, but nobody believed him, so Yellowstone still was not a famous place.