Thousands who traveled the Oregon Trail in central Wyoming were unaware that they were the beneficiaries of a long series of geological events. The granite peaks around you are mountains that rose, sank and then were buried in sand and ashy sediments. Erosion exposed their summits and created the Sweetwater Valley, part of an east-west passageway through the Rockies. The route was used by game animals, Native Americans and fur trappers, followed at mid-century by wagon train and handcart emigrants, stagecoach passenger and Pony Express riders. For some this was the halfway point in a 2000-mile trek from the Missouri River to the West Coast. Arriving here early in July, emigrants celebrated Independence Day. In July, 1841, Jesuit missionary Pierre Jean De Smet wrote of this granite landmark: "The first rock which we saw, and which truly deserves the name, was the famous Independence Rock. It is of the same nature as the Rocky Mountains. At first I was led to believe that it had received this pompous name from its isolated situation and the solidity of its base; but I was afterward told that it was called so because the first travelers who thought of giving it a name arrived at it on the very day when the people of the United States celebrate the anniversary of their emancipation from Great Britain...lest it might be said that we passed this lofty monument of the desert with indifference, we cut our names on the south side of the rock under initials (I.H.S.) which we would wish to see engraved everywhere, and along with a great number of others, some of which perhaps ought not to be found anywhere. On account of all these names, and of the dates that accompany them, as well as of the hieroglyphics of Indian warriors, I called this rock on my first journey 'The Great Record of the Desert."