Built from enough concrete to stretch across the entire country and used to bring power to 1.3 million people across three states, the Hoover Dam is undeniably one of the greatest examples of human engineering. Yet, aside from being an incredible piece of history, the famous dam has also been the subject of some controversy over the years.

For decades, all sorts of freak accidents, ghost stories, and conspiracy theories have surrounded the world-famous structure. Here are 13 such theories and legends that may forever change the way you look at this iconic American landmark!

1. Workers died at the dam: According to one eerie urban legend, some laborers fell to their deaths during the construction of the Hoover Dam. They landed in wet cement, and the dam itself became their tomb.

2. Even a dog died: The truth is that anywhere between 96 and 112 workers—and one very good dog—died during the construction due to all kinds of safety hazards. So, in the end, building the dam was deadly.

3. Satanic symbols marked the dam: Comparisons have been made regarding the Hoover Dam and its resemblance to the throne of Satan. Conspiracy theorists also say that monuments to fallen angels abound the facility, including one resembling the Knights Templar deity Baphomet.

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4. In 2015, an image of a goat jumping over two towers was projected onto the dam. Though it was only the logo of German football club FC Koln, many felt this was particularly suspicious.

Hoover Dam officials claimed they were simply fans of the German club and wanted to test out their new projector system, which was the biggest ever constructed. Still, skeptics alleged the goat logo projection was the work of the Illuminati.

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5. Flood-based relocation: The first time Lake Mead—the name for the reservoir formed by the Hoover Dam—filled up in 1935, the town of St. Thomas, Nevada, became flooded. It forced the Mormon community that had settled there to flee.

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The flood waters reached as high as 60 feet. However, in the years since, droughts have lowered lake levels enough to make the ruins of the town visible and accessible once again.

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6. Fatal cover-ups: Of all of the worker deaths, 42 were attributed to pneumonia. However, many claim that this was allegedly a cover-up for what was actually carbon monoxide poisoning. Why would someone create this sort of story?

Apparently, this elaborate workplace cover-up was created in an effort to avoid paying damages for on-site deaths. Since no one in the surrounding town showed any symptoms of pneumonia, it’s highly likely the illness was a lie.

US National Archives bot / Wikimedia Commons

7. Out-of-this-world theory: You may have heard of the CERN Hadron Collider, the world’s largest particle accelerator. But did you know its powers will be combined with those of the Hoover Dam, unlocking a wormhole through which demons from Saturn will initiate Earth’s invasion? No? Well, that’s what one conspiracy theory would have you believe.

8. Crash landing: In 1943, while testing a new military seaplane, iconic businessman and pilot Howard Hughes crash-landed on Lake Mead. Although he survived, the two other passengers with him did not.

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Lead mechanic Richard Felt’s head was taken off by a propeller that had snapped off after the plane took a nosedive, while Civil Aeronautics Administration inspector William “Ceco” Cline’s body was never found after it was jettisoned from the aircraft.

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9. Unguarded: A former Hoover Dam security guard named Neal Falls was once suspected of being a serial killer, although he was never formally charged with any major crimes in his lifetime. Still, his story was pretty unsettling…

He is believed to have murdered as many as 10 sex workers, until one potential victim shot and killed him in 2015 when he tried to strangle her. It’s possible that more details about his alleged crimes will one day be revealed.

10. Haunted hospital: A hospital was built in nearby Boulder City to provide medical care for Hoover Dam workers, but it closed when the construction ended in 1938. It wasn’t long after that some interesting rumors about the facility began to circulate…

In 2012, the long-since-decommissioned facility was renovated and turned into a community center. That hasn’t stopped the persistent claims of paranormal activity, though; this former hospital is frequently said to be haunted.

11. Continuing dark legacy: The Hoover Dam has seen a number of suicides over the years. It’s not a clean fall; because the dam is sloped, victims tumble down throughout the fall, with horrifying results.

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 12. Haunted hotel: In 1933, the Boulder Dam Hotel opened. It gave visiting dignitaries and members of the aristocracy a place to stay while they were visiting the dam while it was being constructed. However, it was the subject of some concerning rumors…

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Ever since the hotel’s remodeling in 1980, there have been multiple reports of frightening paranormal activity. Not only that, but employees are actually forbidden from ever discussing it!

13. Follow the money: Apparently, if you form a pentagram by folding a $50 bill, you’ll see four obelisks surrounding the Hoover Dam. According to conspiracy theorists, this is evidence that the dam is set to be destroyed…

These strange tales only make the Hoover Dam more fascinating. Whether or not you believe these horror stories, it’s a wonder to behold!

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