In Great Falls of Snake River, Idaho Territory, Thomas Moran presents a stunning landscape filled with vibrant colors. The painting showcases the powerful waterfall cascading down rocky cliffs, surrounded by lush greenery. The sky is painted in soft blues and whites, suggesting a serene atmosphere.

The overall composition draws the viewer's eye towards the dramatic falls, emphasizing nature's grandeur. The painting is executed in oil on canvas, a medium that allows for rich textures and vivid colors. Moran's brushwork is expressive, capturing the movement of water and the ruggedness of the landscape. The dimensions are approximately 100 x 150 cm, making it a sizable work that commands attention.

The use of light and shadow adds depth, enhancing the three-dimensionality of the scene. Thomas Moran was a key figure in the American Romantic movement, known for his breathtaking depictions of the American West. This painting, created in the 1880s, reflects his fascination with the natural beauty of the region. An interesting fact about this work is that it played a role in the establishment of Yellowstone National Park, as Moran's art helped to promote the area's stunning landscapes to the public and lawmakers.