This is a satellite image of Area 51, Southern Nevada, a remote detachment of Edwards Air Force Base, collected on February 26, 2013. (DigitalGlobe/DigitalGlobe/Getty Images)

The last time I visited Area 51, it didn’t exist.

But as of this week it does. Officially.

For reasons unknown, the government finally has admitted that Area 51 — the Shangri-La of alien hunters and a sturdy trope of ­science-fiction movies — is a real place in the Mojave Desert about 100 miles north of Las Vegas.

It presumably does not house hideous squidlike ETs, but at least you can see the place on a map. Area 51 is confirmed in declassified CIA documents posted online Thursday by the National Security Archive at George Washington University. A dogged researcher pried from the CIA a report on the history of the U-2 spy plane, which was tested and operated at Area 51.

The military, which runs the base, always denied that Area 51 was called by its famous moniker, preferring a designation connected to the Groom Lake salt flat, a landing strip for the U-2 and other stealth aircraft.

“Your honor, there is no name,” an Air Force attorney told a federal judge in 1995. “There is no name for the operating location near Groom Lake.”

The hearing was part of an environmental poisoning case brought by Area 51 workers who said that they had been sickened by exposure to toxic chemicals — including anti-radar coatings and other classified materials — burned in open pits on the base.

For years, those workers commuted from Vegas to Area 51, also known as “the Ranch.” Some of them died after developing strange rashes and respiratory problems.

The men could tell no one what they did; they had signed national-security oaths barring any disclosures about the black-budget facility, where the stealth bomber also was tested. But some became plaintiffs in a case against the government brought by George Washington University law professor Jonathan Turley.

That case brought me to Area 51 in 1997. I had hoped to see the base from afar. From certain vantage points, I’d heard that it might appear, suitably, like a mirage.

But I didn’t make it past the perimeter, where a sign warned that trespassers fell under the jurisdiction of military law. Too dangerous: “Use of Deadly Force Authorized,” the sign said, citing the Internal Security Act of 1950.

In 1955, President Dwight D. Eisenhower “approved the addition of this strip of wasteland, known by its map designation as Area 51, to the Nevada Test Site,” according to the declassified CIA history. The area was near the Atomic Energy Commission’s vast, desolate proving grounds.

The CIA internally published its official history of the U-2 program in 1992. It was released in heavily redacted form thereafter, and National Security Archive fellow Jeffrey Richelson reviewed a copy in 2002. He filed a new Freedom of Information Act request in 2005 and the documents arrived about a month ago, this time with fewer redactions. Therein, the first-ever reference to Area 51.

Why was the veil finally lifted?

“It is something we do not know the answer to,” Richelson said Friday. “One of the things I want to find out is the genesis of this decision: Why did they not redact it?”

Back in the 1990s, the Clinton administration fought fiercely to prevent the Area 51 workers from going forward with their case. President Bill Clinton signed an order exempting Area 51 from disclosing its pollution records, although the Environmental Protection Agency did do an inspection. Of course, it was never called Area 51.

Eventually the plaintiffs won a Pyrrhic victory. Turley prevailed in proving that environmental laws were violated at Area 51. “They were forced to clean up the facility,” he said Friday.

“It was a major victory legally, but it felt quite incomplete,” Turley said. “The workers received nothing but the satisfaction of knowing the facility was brought up to compliance.”

They had hoped at least to have some of their medical expenses paid for by the government.

The secrecy surrounding Area 51 amplified conspiracy theories claiming it was infested with extraterrestrials — a notion popularized in movies such as “Independence Day” and, more recently, “Super 8.” The UFO angle emerged because, for decades, people reported seeing strange lights in the surrounding desert — presumably secret aircraft taking off and landing in Area 51.

Now that Area 51 officially exists, does that ruin its mythical utility for Hollywood creature features?

The clandestine base always was a reliable haven for horrifying Monsters from Beyond.

Veteran sci-fi author Harlan Ellison — who worked on the original “Star Trek” and “Babylon 5,” among other shows — says filmmakers will always find new tropes.

“The human race has a psychopathic need to create gods and mysteries,” he said. “Demystifying Area 51 is like saying, ‘Gee there might not be a Bigfoot.’ . . . By now, only the most lame-brained think we are regularly visited by aliens and that they are at Area 51.”

The next big Area 51 movie is awaiting release. It is ingeniously called “Area 51.” The plot, per the Internet Movie Database, is simple:

“Terror strikes when reporters visit a secret base that houses extraterrestrials.”

I’m sure it’s long since been cast, but it would be an honor to play a scribe who has been there and is eager to face the slimy maw of a squidlike alien.