11 Most Endangered Historic Places

Prehistoric Serpent Mound

Year Listed: 1993
Location: Ohio
Threat: Public Policy


Serpent Mound, an earthwork in the form of a coiling, 1348-foot-long snake, is the puzzling legacy of a Native American culture long vanished. Archaeologists and historians are not certain who built it, when, or why. First surveyed in 1846, later purchased by Harvard University and eventually turned over to the Ohio Historical Society, this curious effigy was one of the first archaeological sites in the United States to be opened to the public. The mound overlooks the Ohio Brush Creek Valley, the proposed site of a resort complex, golf course, conventions center and 100-acre manmade lake. Scientists state that the lake waters would erode the bluff on which Serpent Mound was built, inundate archaeological sites and preclude further study to unlock the meaning of this mysterious landmark from the ancient past.