There's a 386 meter long monument shaped like a snake in
Adams County
European pioneers in the 1700 assumed it might be some
leftovers from Atlantis, people of Noah or even
Israels lost empires? (stammer). This might be a source
of why the Book of Mormon claims europeans have lived in 
America long before colombous found it.

Later they concluded this monument (named Serpent Mound)
was indeed made by native americans.