Archaeologists have uncovered many unique pieces of art and tools over the years that help us understand human history.
But some people believe they could be telling us more about life beyond Earth.
It's well documented that many believe the Pyramids and Stonehenge were made extraterrestrials but early artwork from the Mayans and Aztecs to objects found high in the mountains are also seen to be early representations of life in space.
These are the most compelling cases from around the world.
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