Every year in mid July, many of the world’s most powerful men convene at a private, 2,700-acre campground in Northern California for two weeks of ribald revelry and pagan ritual. This is not a conspiracy theory, or the plot of a Hollywood movie. You haven’t heard about it (or if you have, you know next to nothing about it) because the degree of secrecy surrounding this annual event rivals the budget of the NSA. Known attendees include former U.S. presidents and many other heads of state and titans of the business world. Although “outside cares” are officially unwelcome, many plots have been hatched there, such as the Manhattan Project, which ultimately led to the invention of the atomic bomb. Although security is infamously tight, a few intrepid outsiders have managed to infiltrate the event and bring back photos, reports, and even footage of the orgiastic partying and strange rites conducted there. This extremely rare archival photo is just one example. Exactly what it depicts is anyone’s guess, but more photos can be found here.