The Mutual UFO Network–better known as MUFON–is the world’s leading organization devoted to the scientific investigation of unidentified aerial phenomena and other unexplained encounters. With more than five decades of investigations, could MUFON’s extensive database contain definitive proof of extraterrestrial visitation?

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Ancient Aliens is counting down the world’s top ten pyramid sites, from a valley in Peru with over 250 hidden pyramids to an ancient Greek city with mysterious 4800-year-old ruins to Egypt’s famous Giza Plateau. Could the extraordinary structures that stand at these sites provide evidence of extraterrestrial visitation?

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The towering obelisks of ancient Egypt weigh hundreds of tons and each was perfectly carved from a single granite rock. While mainstream scholars identify them as monuments to the pharaohs, Ancient Astronaut Theorists suggest they may have served a technological purpose–they powered a technology that allowed for communication with the gods who came from the stars.

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The discovery of the ancient megalithic site of Karahan Tepe in southern Turkey turned the world of archaeology on its head, displaying engineering skills far beyond what the people of the time were thought to be capable of. But could new evidence reveal that this more than 11,000-year-old complex was built not by humans…but giants?

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Ancient Aliens has examined the oldest and most mysterious rock art on Earth–up close and in person. Now, Giorgio Tsoukalos takes a look back at the incredible hieroglyphs, petroglyphs, and geoglyphs that he believes tell a worldwide story–of alien visitation.

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More than 10,000 crop circle formations have been documented in over 50 countries, and many display properties that defy conventional explanations. Are they of otherworldly origin? And if so, what is their purpose? Could it be that reconnection with our alien ancestors will only come when we finally crack the crop circle code?

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Studies have shown that up to 70% of all UFO sightings happen in so-called ‘hotspots’ where reports of visions, mysterious lights and unusual phenomena are regularly witnessed–and not only in modern times, but dating back thousands of years. Could there be something about these locations that attracts extraterrestrial visitors?

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Ancient Aliens has followed investigators across the globe as they’ve gone directly to the sites where unexplained incidents have been reported. Now, Giorgio Tsoukalos takes a look back at the most extraordinary encounters that, as far as he’s concerned, provide evidence of an extraterrestrial presence on Earth.

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