WASHINGTON — It’s been called the Woodstock of Potomac, Maryland.

Thirty years ago, thousands of people converged upon the Full Moon Jamboree, a two-day outdoor concert on a farm off River Road.

Now, the event is remembered in the new documentary “Heavy Metal Picnic,” which screens at 7:30 p.m. Friday at the AFI Silver Theatre in Silver Spring, Maryland.

The film is directed by Jeff Krulik, who previously co-directed the 1986 documentary short “Heavy Metal Parking Lot” (1986).

Mark Segraves of our TV affiliate NBC-4 reports in the video below: