This photograph is of Windsor Lake in the San Isabel National Forest near Leadville in Lake County, Colorado. Trees surround the deep blue lake. Mountains sit under a cloudy blue sky in the background. This photograph can be found on page 73 of John Fielder's Book, Colorado 1870-2000 Vol. II.
The black & white photograph, taken by William Henry Jackson, 86.200.557 is found on page 72 of John Fielder's book, Colorado II 1870-2000.