Archaeologists in 1991 opened a trench first
cut by the Putnam excavaton in the late 1800s
and recovered organic materials from the undisturbed edge of
the trench. Radiocarbon dating placed construction
at about 900 years ago, over a millenia later than once thought
based on association with the nearby Adena burial mounds (image
Next below is the tail of the serpent with the GPS
receiver along the west edge.
Mound sits within an oblong crater where a massive extraterrestrial
object collided with the earth.
The crater overlaps Adams, Pike and Highland counties, and the mound
is near the
five-mile-across crater's southwest
The topography around Serpent
Mound is jumbled, and impact theory explains why for many geologists.
Boreholes samples show microscopic cracks in quartz crystals and horsetail-shaped
fracture shatter cones, patterns resembling nuclear reactions. Iridium
is high in the area.
of the burial mounds near Serpent Mound.
Serpent Mound GPS-determined coordinates.
Serpent Mound Burial Mound
Serpent Mound Oval Mound
Serpent Mound Tail
The Oval Mound at Serpent Mound is situated
precisely one degree west of Newark Circle while the longitude
difference with Newark Octagon equals circumference/365.
Map reoriented to accurate north.
Click for larger map.