The USGS Photographic Library in Denver, Colorado is an archive of still photographs and original sketches dating from the 1870’s and taken by USGS scientists as part of their field studies. Topics include USGS personnel, earthquakes, volcanoes, geologic hazards and other phenomena, historical mining operations, and earth science photographs. The works of pioneer photographers such as W.H. Jackson, T.H. O’Sullivan, Carleton Watkins, J.K. Hiller, Thomas Moran, A.J. Russell, E.O. Beaman and William Bell are represented in the collection. Some photographs have been used to illustrate publications, but most have never been published. Selected photographs from the collection can be accessed online from the USGS Photographic Collection web site.