Aquia Landing Slides a Powerpoint slide show with pictures of Aquia Landing and some useful maps, but I believe they have the location of Yuba Dam and Burnside's wharf backwards.
Aquia Exposed a view of the pier remains at Aquia
The Evolution of Aquia Landing A nice summary of Aquia Landing.
The Railroad Bridges over Potomac Creel - Bean poles and trusses The comments that accompany this post are quite good and include links to the original hand written letter Herman Haupt wrote describing why he built the trestle.
I reported this incident in my earlier post, Haupts encounter with Hooker, but this link will take you to scans of the original letters.
Washington Woolen Mill also provides a lot more information about this mill that I mentioned in an earlier post. It was actually in Fredericksburg, but I may relocate this to Brook on my layout. I already have an N Scale model of the Charlottesville Woolen Mills that I could use in the background for forced perspective, or I could build a model of the Washington Woolen MIll mill.