https://www.loc.gov/resource/gvhs01.vhs00125/
LOC
Regional map of Virginia, Maryland and Pennsylvania showing the Potomac River and its tributaries. Robert Knox Sneden, c 1861. LOC.
Regional map of Virginia, Maryland and Pennsylvania showing the Potomac River and its tributaries. Robert Knox Sneden, c 1861. LOC.
https://www.loc.gov/resource/gvhs01.vhs00125/