CSX/Southern Bridge over Potomac River at Washington DC

(Bridge Hunter, Satellite)

William A. Shaffer added
Crossing a River
The "Cardinal" has just crossed a river with Washington's skyline in the background. (Photo by William A. Shaffer)

Given that Washington is in the background, the river is wide, and there is a swing span in the bridge, it was pretty easy finding the bridge. Bridge Hunter normally lists predecessor railroads. But not in this case. My best guess based on my 1928 RR Atlas is Southern. Looking at a route map confirms that the Cardinal does goes rather far south before it starts working its way north to Chicago.

Interactive Map

Then I remembered that this route was formed to make a powerful senator happy. I think it was a West Virginia senator. The fact that CSX gutted the B&O across southern Ohio is probably what forced rerouting the Cardinal.