On Jan. 20, 1969, Led Zeppelin performed a show for less than 60 people at the youth center in Wheaton, Md., a town with a population under 50,000 near Washington, D.C. Or, maybe and more likely ... they didn't.

You see, despite the fact that a hardcore group of "attendees" or believers have stuck to this story for over four decades now, Led Zeppelin's official site lists the show only as an "unconfirmed rumour," and notes that the band's road manager, Richard Cole, has no memory of it either. Further, nobody has ever been able to produce a photograph, contract, ticket stub, gig poster or any other physical evidence to prove that the band did in fact perform there.

Still, the local legend has endured, and inspired filmmaker Jeff Krulik -- co-creator of the immortal Heavy Metal Parking Lot -- to film the investigative documentary Led Zeppelin Played Here, which played in unfinished form at various film festivals.

Back in 2009, Krulik invited everyone who said they had been at the 1969 Zeppelin show to a reunion. Funnily enough, according to a Washington Post report, twice as many people showed up for this event as had supposedly attended the original concert. Of those, only about a half-dozen claimed to have seen the show, and the only evidence presented was a pair of battered sneakers apparently worn that night.

Still, the true believers were undaunted by the lack of evidence. "They were definitely here," declares alleged attendee Anne Marie Pemberton. "(Jimmy) Page was over here. John Paul Jones was over there. [Robert] Plant the showman was right here. And right behind was John Bonham with his hellacious drum set."

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