The past holds so many secrets. I think the human race is finally starting to realize we don't know everything there is to know about our history. Yet, scientists and historians alike are very stubborn when something new is discovered and they don't like it when something challenges the currently-accepted worldview. Here are some discoveries from the ancient world that don't play nicely with our currently-written historical record... The Nebra Sky Disk Discovered by treasure hunters, the Nebra Sky Disk has been called the most important archaeological discovery of the 20th century. It was found in Germany and while some thought it was fake, it was later not only found to be authentic, but it was also 100 years older than the world's oldest depiction of the night sky found in Egypt. Its discovery is significant because until its discovery, it was believed that the center for astrological knowledge has been in the Middle East, and that the inhabitants of Europe were mostly barbarous with little to no understanding of the stars. Precision Stone Cutting in Peru How did ancient peoples construct the giant stone wall at Saksaywaman in Cusco, Peru? For that matter, how did they manage to make such precision cuts in the stone to the point where the blocks fit so well, absolutely no mortar was required? Antikythera Mechanism The Antikythera mechanism, an ancient mechanical analog computer, was discovered in 1902. The artifact was recovered from the Antikythera shipwreck off the Greek island of Antikythera and is believed to have been designed and constructed by Greek scientists as far back as possibly 205 BC. It was apparently used to predict astronomical positions and eclipses for calendrical and astrological purposes. Ohio Decalogue Stone Discovered in 1859, the Decalogue Stone was found buried beneath the largest known mound in North America. Inside an outer casing was Decalogue Stone, which featured a complete rendition of the Ten Commandments ancient Hebrew text. Some thought it was real while others thought it was fake, mostly because, according to the history books, no one from Europe or the Middle East was in America prior to Christopher Columbus. Dropa Discs The Dropa Stone Discs were supposedly found inside of a cave in the Himalayan mountains by a professor of archaeology and students. The 716 mysterious stone discs are finely decorated with a series of tiny glyphs which are so small that they can only be seen with the aid of a magnifying glass. A definitive translation is still not available. Since the glyphs seem to be linked to an as-of-yet unknown language, the true meaning of the glyphs and the stones themselves remain a mystery. Since the time of their supposed discovery, the stones have never been displayed in any museum and some people believe the entire story to be a hoax. Mesas are Tree Stumps Perhaps one of the most elaborate and jaw-dropping alternative history theories is the one propounded recently which suggests that mesas in the Southwestern United States are actually tree stumps from a time when trees grew to unimaginable heights in a long-lost fairy tale epoch. And while this theory hasn't been proven, some of the large stone objects demonstrated in the video below seem to show a hexagonal structure that closely resembles the biological structures found in trees. The very process of petrification is brought into question because after all, when was the last time you heard about a human body turning into stone after death?