The Air Force military installation at Groom Lake in southern Nevada has been the subject of some intense conspiracy theories for decades.

Folklore around the strictly prohibited and barbed-wire-laced Area 51 continues to pin it as a site of extraterrestrial interest, with reports of UFO sightings and aliens to boot over the years.

Adding to its mystery, its operation has been kept under wraps with little of us having any clue what actually goes on in the desert spot that sits around 83 miles from Las Vegas.

Back in 2019, a Facebook event invited dozens to 'storm Area 51' with the tagline: "They Can't Stop All Of Us," and although some actually stuck to their guns and turned up, no one actually managed to get inside.

So what on Earth is it actually there for?

Well, it's a US Air Force (USAF) test facility.

Way back when the site was first acquired by the USAF in the 1950s, the military conducted testing for aircraft, such as the U-2 spy plane.

This is a high-altitude reconnaissance plane, which can operate above 70,000ft, in the stratosphere.

And given that Area 51 is such a highly secretive Air Force base, it isn't much of a surprise that it has become a hotspot for alleged sightings of unidentified flying objects.

Documents that were released following a Freedom of Information Act request in 2013 even discussed the U-2 specifically.

The documents said: “High-altitude testing of the U-2 soon led to an unexpected side effect - a tremendous increase in reports of unidentified flying objects (UFOs).”

They added: “U-2 and later Oxcart flights accounted for more than one-half of all UFO reports during the late 1950s and most of the 1960s.”

The U-2 became central to US intelligence gathering during the Cold War, being used to observe the Soviet Union, China and Cuba.

It had its heyday back in the Cuban Missile Crisis, playing a crucial role when the Soviet Union stationed nuclear weapons on Cuba.

The intense standoff saw 35-year-old U-2 pilot Rudolf Anderson from South Carolina die in the conflict when the jet was shot down over Cuba in 1962.

The configuration of the wings, designed for high altitude flight, also means that the plane effectively has to be stalled in order to land.

But the speculation about creatures from outer space being connected to the site isn't too far-fetched either, as the aircraft had to operate at such high altitudes that pilots had to wear specially designed spacesuits to survive the difference in the atmosphere.

So, there's the somewhat boring answer: Area 51 was used to test experimental aircraft during the Cold War when secrecy on US intelligence was the utmost priority.

Though that doesn't mean aliens don't also have an interest in checking it out either, does it?