Great Serpent Mound, Ohio

The sinuous shape of the serpent is seen here.  It has a circular shape in it's mouth, thought to be an egg, universal symbol of fertility and new life.  The serpent is 1330 ft. long, making it the largest earth work effigy in the world.  No cultural artefacts have been found in the mound, thus making it  difficult to date; but it is generally attributed to the Adena or Ancient Fort native cultures, and placed somewhere between 900 BCE and 1550 CE. 

The head of the serpent is aligned to the summer solstice sunset, and the placement of the serpent is where three distinct types of soil converege, and where there is an unusual type of bedrock formation called a cryptoexplosion, thought to be formed by upheaved magma or by a meteorite strike.