THIS IS A MUST CHECK OUT!
The AMERICAN CIVIL WAR, THEN AND NOW.
These comparison photos of modern-day locations juxtaposed against original photos from the war are unique in their presentation. To the right of each photo is a slider that, when using your mouse, can be dragged at your own pace back and forth to compare the THEN and NOW. Give this one a viewing. Well worth the time.
See The AMERICAN CIVIL WAR, THEN AND NOW here: