Located at the north end of Washington Reagan National Airport's main runway (and along the Potomac River), Gravelly Point offers the best view of planes taking off and landing -- just a few feet over your head (think Wayne’s World!).  It's perfect for a picnic lunch!  Gravelly Point just off the GW Parkway, though be warned that parking can be tough on the weekends, and the park does close at dark.
                        
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