Green River Cliffs, Wyoming by Thomas Moran https://www.nga.gov/artworks/82648-green-river-cliffs-wyoming
In June 1871, Thomas Moran, a gifted young artist working in Philadelphia, boarded a train that would take him to the far reaches of the western frontier and change the course of his career. Just a few months earlier he had been asked to illustrate a magazine article describing a wondrous region in Wyoming called Yellowstone—rumored to contain steam-spewing geysers, boiling hot springs, and bubbling mud pots.
Instead, the dazzling colors of the sculpted cliffs and an equally colorful band of Indians