13 Hidden Historical Sites in America More Fascinating Than Mount Rushmore

2. The Serpent Mound: Mysteries of Ancient Earthworks

In the rolling hills of Southern Ohio lies the Serpent Mound, an effigy mound that stretches over 1,300 feet, shaped like a serpent with a coiled tail. This prehistoric site is believed to have been constructed by the ancient Adena culture around 1000 B.C., although some theories suggest it was built by the Fort Ancient culture around 1070 A.D. The mound’s purpose remains speculative, with theories ranging from it being an astronomical calendar to a ceremonial site. Its precise construction and alignment with celestial events speak to the advanced understanding of astronomy by its builders, offering a glimpse into the ingenuity of ancient Native American cultures.