C&O Canal: Make a day of hiking or biking part of this historic and scenic canal along the Potomac. Hardier souls could do the whole C&O, but with the canal running 184.5 miles, better plan on making a weekend of it.

Spruce Knob/Seneca Rocks National Recreation Area: Venture into West Virginia to this scenic site at the headwaters of the Potomac, where water first starts to flow from West Virginia to the Chesapeake Bay. Spruce Knob/Seneca Rocks features the highest peak in West Virginia, excellent rock climbing and breathtaking views.