Ohio has awesome mounds. Thanks Beeches. About 200,000 total in North America at one time

There are two in particular. The great octagon and circle at Newark (on the golf course) and another at High Banks.

Basically they are the same design created 90 degrees apart on so that they can accurately site lunar and solar activities at different latitudes (where they are physically). High Banks has a larger circle.

Newark octagon and circle is very fascinating. The octagon has 8 mounds inside at the internal angles (which are 135 degrees each). The circle could be folded over and rest on the 8 mounds..circling the octagon.

So it utilizes among other things 8 and 13, just as the Great Pyramid at Giza does with its 8 sides built on 13.1 acres and 481 feet high - 4+8+1=13.

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