Area 51 has been called the most secret place on Earth that never existed. And for a long time, that was true.

On March 26, the Smithsonian-affiliated National Atomic Testing Museum in Las Vegas plans to unveil the first-ever Area 51 exhibit, and it will be loaded with UFO and possible extraterrestrial-related items.

The exhibit, dubbed "Area 51: Myth or Reality," will present the historical records of a place that has long been shrouded in mystery.

Watch this Area 51 exhibit promo video:

"The CIA declassified most of the records on Area 51 up through the late '60s and early '70s. It's out in the public now," said museum CEO and executive director Allan Palmer.

"Now we know a lot more about it and can present some of the really true stories that happened out there. And we feel a bit of an obligation to tell the larger story about the public's perception of Area 51, which runs right into aliens, UFOs and extraterrestrial time travel, and those kind of things," Palmer told The Huffington Post.

For years, UFO conspiracy theorists have claimed that the U.S. military was using a secret facility in the Nevada desert to examine captured flying saucers. Fuel was added to that fire when many people reported seeing strange craft in the skies around the mountains that surround an actual military base, located near a salt flat called Groom Lake, about 80 miles north of Las Vegas.

It's now widely known that Cold War spy planes (including the U-2) were developed and tested at the base. The man who broke the story in 1989 about alleged alien technology at Area 51 was Emmy Award-winning news journalist George Knapp of KLAS-TV in Las Vegas.

"There had been bits and pieces in aviation publications about the possibility of something really weird flying around there, but nobody had done any serious reporting about it," Knapp told HuffPost.

In 1989, Knapp met Bob Lazar, who claimed to be a physicist employed at an area of the base named Sector Four, or S-4. As the tale goes, Lazar alleged that this secret military facility was used to study several alien spacecraft, with the ultimate goal of trying to reverse-engineer the technology to figure out how it worked.

"There are questions that I have about Bob," explained Knapp, "and I know there are problems and gaps within his story, but there were a lot of things that Lazar knew about the base that are really difficult to explain. For example, he knew there was a place called S-4, and that had never been printed anywhere."

The Bob Lazar story unfolds here:

Prior to the news series that Knapp reported on Area 51, the world had never heard of the place. Only the people who worked there or lived in the area knew about it. Unless you had a specific connection to the activities there, you wouldn't have known the place existed.

The National Atomic Testing Museum -- the nation's newest national museum -- decided to combine the true stories of those who actually worked at Area 51 with the speculative reports of an extraterrestrial element.

Because of his key role in putting the secret facility on the map, exhibitors asked Knapp to be involved. To that end, a special George Knapp room has been included in the exhibit, where visitors can see a variety of documents and artifacts that he’s collected over the years: films, videos, photos and something very special to be unveiled for the exhibit opening.

In 1986, an unidentified object streaked across the sky over Dalnegorsk, USSR, and crashed into Mount Izvestkovaya, also referred to as Height 611.

Through many contacts and great effort, Knapp obtained some of the strange materials actually gathered at the scene of the crash.

"I'll give you a hint," he said. "We've often heard the argument from the naysayers that there's nothing to study, no evidence. This famous case happened in Russia where scientists went to the scene of a very dramatic incident and collected samples, and they gave me some of them!"

Some have referred to the crash as the Russian Roswell, referring to the famous 1947 crash of an alleged alien craft in New Mexico and the subsequent cover-up of facts surrounding the case.

The public will have a chance to see what Knapp brought back from Russia and decide for themselves if it's Earth-based or out of this world.

Area 51: The top secret military test base that never existed: (story continues below)

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The entire museum documents the shared Cold War history between the U.S. and the old Soviet Union, running from the end of World War II to the present. In 1950, President Harry Truman set up the Nevada Proving Ground, which evolved into the Nevada Test Site, created to test nuclear weapons in order to keep up with the Soviets.

Visitors to the Area 51 exhibit will see artifacts and other pieces of the secret facility's history.

"When you first go in, you're going to be treated like a new recruit to Area 51," said Palmer, who has the rare distinction of being a highly decorated combat jet fighter pilot for both the Air Force and the Navy.

"You'll be left to decide what you think is the true story about the place: Is it aliens, UFOs, intelligence? What's all this about? And that's what we're going to expose them to.

"Sometimes what you see is not always what's real. And that may be true the other way around," Palmer added. "What you may think are just ordinary, regular things might be extraterrestrial or visitors from other places. Who knows?"