In an article written by Dudley Garden for Wyohistory.org:
"Sweetwater County, Wyoming, nearly twice the size of Connecticut and just 64 square miles smaller than Massachusetts, is marked by buttes and mesas, canyons and wide expanses of basin brush. It is Wyoming’s largest county, by area. Table Rock, Pilot Butte and the Boars Tusk are its most famous landmarks, but places like Black Rock and North and South Table Mountain are equally striking.
It is the Green River Canyon, however, that came early on to symbolize the West and its vastness. Artist Thomas Moran's “Green River Cliffs, Wyoming”, 1881, captured the essence of the landscape that is Sweetwater County. In the painting, stark cliffs in bright hues open the view to a land that stretches away west and north towards the river source. Moran shows us a place few understand but nearly all fall in awe of when they first see it.
The artist painted these cliffs on the Green several times, and always put them at the core of his composition. These are the cliffs a person sees today north of the highway when driving past Green River, Wyo. on Interstate 80. With their ever-changing colors, they reflected the angles of the sun in Moran’s paintings and served as the backdrop for open spaces. He often set American Indians in the foreground as the essential element in a world of openness and possibility."