The Newark Earthworks: A Geometry That Aligns to the Moon

Four square miles of earthwork enclosures built two thousand years ago in central Ohio. The Great Circle at Newark is twelve hundred feet across. The Octagon Mound is one of the most precisely aligned astronomical structures in the pre-Columbian Americas.

The alignment is to the eighteen-point-six-year lunar standstill cycle, the longest cycle in the moon's movement as observed from the earth's surface. Scholars have confirmed that when viewed from the observatory mound at the center of the Octagon, the moon rises within one-half of one degree of the octagon's exact center at the peak of that cycle. This precision was achieved without telescopes, without written mathematics as Europeans understood it, and without metal tools. It was achieved through sustained, multigenerational observation and the translation of that observation into the landscape itself.

The Hopewell culture that built these earthworks flourished from roughly one hundred before the common era to five hundred of the common era. They were not a single people but a network, trading obsidian from Wyoming, copper from Lake Superior, and shark teeth from the Gulf of Mexico. They built across a large swath of what is now Ohio, Indiana, and Illinois.

In twenty twenty-three, the Newark Earthworks and the Hopewell Ceremonial Earthworks more broadly were designated a UNESCO World Heritage Site.

For decades, the Octagon Mound, the centerpiece of the Newark complex, was occupied by a private golf course while the Ohio History Connection pursued legal access to the site. The golf club's lease ended in early two thousand twenty five, after the Ohio Supreme Court upheld the push to reclaim the land for public access.