Here is a previously undocumented photograph of Libby Prison in Richmond, Virginia. The second-most infamous prisoner-of-war camp in the Confederacy (after Andersonville), it housed Union officers and had an appallingly high mortality rate. For more information on the prison and its history, check: Libby Prison.
This view is most probably post-war, as most of the photos of the building even in 1865 show the whitewash on the lower levels as intact, and the Libby Prison sign in place hanging over the downhill sidewalk from the upper street facade.
After the fall of Richmond to Union forces, the prison was used to house Confederate officer prisoners of war, this time with greatly improved physical conditions to include windows with panes in them. Later, it became a museum, and was even dismantled and re-assembled in Chicago, but when it failed as a tourist attraction, the materials of the building were sold off as souvenirs.
As you can see the image was exposed to fire at some point, with scorching around the edges. I’m guessing the age to be between 1870-1880.
Here is a photo from the National Archives that shows the prison in 1865.