Aerial techniques have been proven effective for archaeological reconnaissance in several parts of the world.

This paper describes photoarchaeological techniques which were used in a survey of a section of the Potomac River, near Washington, D.C. Thirty-six stone structures and one major Indian village site were discovered. The stone structures were primarily stone fish traps and fish weirs. One of the structures was found to be a navigation weir, constructed by the Potowmack Company, founded by George Washington in his efforts to open up the American "Western Frontier," regions in Maryland and Pennsylvania.

Physical descriptions and locations of the structures are listed on the following pages, together with a comparative analysis of the structures. A recommendation is made for a site designation system which strengthens the standard Smithsonian system by adding Universal Transverse Mercator coordinates to them, thus simplifying location designation.