Americas Stonehenge also known as Mystery Hill in Salem NH is a prehistoric location once thought to have been built by Pre-Columbian Settler. Others think it to be a hoax created by the Pattee Family.
My favorite theory is it is a calendar intended to mark off the seasons for planting, harvesting, and preparing for winter.
There are points over the location which coincides with seasonal equinoxes and solstices. Radiometric dating indicates it is over 4,000 years old. the drift of the North stone alignment also lines up with astronomical drift.
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