Manassas National Battlefield Park - http://www.nps.gov/mana

Site of two Civil War battles between the Union and
the Confederacy in the American Civil War. The first
battle took place early in the conflict, with most
participants, and many DC residents who came to watch
what they thought would never become as bloody as it
did, believing this would be a minor skirmish and
the conflict would quickly simmer down...

One photo of note can be viewed at http://www.pbase.com/ambadale/image/56484159 -
it's of a memorial marker for the fallen son of Senator Daniel Webster.