Geologist Ferdinand Hayden at work with a rock hammer. USGS photo by William Henry Jackson, 1870.
Images
Images of Yellowstone.
![Geologist Ferdinand Hayden at work with a rock hammer in 1870](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/media/images/Hayden%20photo.jpg?itok=xhiWmW8o)
Geologist Ferdinand Hayden at work with a rock hammer. USGS photo by William Henry Jackson, 1870.
![Henry Wood Elliott during a geological expedition in 1870](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/HenryWoodElliotUSGS-WHJackson1870.jpg?itok=liHstI93)
Henry Wood Elliott during a geological expedition in 1870. Photo by William Henry Jackson.
Henry Wood Elliott during a geological expedition in 1870. Photo by William Henry Jackson.
Undated portrait of Jim Bridger (1804-1881). Published in Gaston's Portland, Oregon: Its History and Builders, volume 1 (1911), image in the public domain.
Undated portrait of Jim Bridger (1804-1881). Published in Gaston's Portland, Oregon: Its History and Builders, volume 1 (1911), image in the public domain.
![William Clark's 1814 map, John Colter route through Yellowstone](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/masonry/public/thumbnails/image/Colter.jpg?itok=1EyJ22ro)
William Clark's 1814 map, indicating the route of John Colter during the winter of 1807-1808. (Library of Congress, Geography and Map Division, Washington, D.C.)
William Clark's 1814 map, indicating the route of John Colter during the winter of 1807-1808. (Library of Congress, Geography and Map Division, Washington, D.C.)