July: Patuxent NWR Cash Lake Loop Laurel MD: From the Baltimore Washington Parkway take the exit for Powder Mill Road. Go east on Powder Mill to the entrance for the Patuxent National Wildlife Visitor Center on the right. The road name is Scarlet Tanager Loop. Follow this to the visitor center where there is a large parking lot. (Lat: 39.0273 Lon: -76.79845)
The waters of the Potomac in Washington, DC. linked on C & O canal to the headwaters of the Ohio River was begun by John Quincy Adams in A dream that Jefferson had, but didn't live to see like the Canal du Midi he saw in France.