It's where some of the most innovative military aircraft ever built by Lockheed Martin Corp. were flight tested. Supposedly.
For decades, the government had refused to confirm the existence of the military outpost, which is about 100 miles outside of Las Vegas. Until now.
The newly declassified history of the U-2 program is documented in the papers obtained under the Freedom of Information Act by Jeffrey T. Richelson, a National Security Archive senior fellow at George Washington University.
Audrey Hewins, an Oxford, Maine, woman who runs a support group for people like her who believe they have been contacted by extraterrestrials, said she suspects the CIA is finally moving closer to disclosing there are space aliens on Earth.
"I'm thinking that they're probably testing the waters now to see how mad people get about the big lie and cover-up," she said.
It's known that Area 51 was created during the Cold War so that the military could test cutting-edge projects like the U-2 spy plane, the SR-71 Blackbird and the F-117 Nighthawk without worrying about being discovered.
There have been numerous historical essays and books published about the site - even photos. But because of the new documents, the accuracy can be verified, according to Richelson.
The documents show numerous references to Area 51 and Groom Lake, with a map of the area.
Area 51 has been ground zero for conspiracy theorists for decades. Flying saucers. Bug-eyed aliens. Staged moon landings.
In truth, Area 51 was the proving grounds for Lockheed's biggest programs, including the high-flying U-2 spy plane that was first designed during the Eisenhower administration to breach the Iron Curtain and, as engineers said, snap "picture postcards for Ike" of hidden military strongholds in the Soviet Union. The jet still flies today.
The SR-71 Blackbird flew reconnaissance missions starting in 1966 at speeds exceeding Mach 3 and altitudes of 85,000 feet. The last SR-71 mission was in the spring of 1995.
It remains a technological marvel. On Sept. 1, 1974, an SR-71 flew from New York to London in 1 hour, 54 minutes, 56 seconds. It beat the previous trans-Atlantic speed record by nearly three hours.
Lockheed also built the F-117 Nighthawk, the world's first radar-evading aircraft, which attacked the most heavily fortified targets in Iraq during Operation Desert Storm in 1991. It was the only coalition jet allowed to strike targets inside Baghdad's city limits.
And those are just the Area 51 aircraft we know about.
Richelson's quest for answers goes back years. He first reviewed the CIA's history of Area 51 in 2002, but found all mention of it redacted. Three years later, he requested another version of the original 1992 report.
Last month he got his reply: a new copy of the 400-page report with all mentions of Area 51 restored.
He says the new document shows the CIA is becoming less secretive about Area 51's existence, and that bodes well for future information requests about the Cold War weapons race.
"Now you can read in some detail about U-2 missions of the past," he told the Times. "We always knew there were 24 U-2 missions over the Soviet Union but it's nice to have maps and a table with each pilot's name and each payload.
"Hopefully further information about those classified missions will come out in time."
The Associated Press contributed.