🇺🇸 United States · Earthwork
Monks Mound
Mississippian 900–1200 CE (peak 1050–1200) · Mississippian (Cahokia)
Largest earthen structure in the Americas north of Mexico and centerpiece of Cahokia Mounds State Historic Site.
🇺🇸 United States · Earthwork
Hopeton Earthworks
Middle Woodland Hopewell 100 BCE–500 CE · Hopewell tradition
Hopewell 22 ha circle-square with 321 m Great Circle, UNESCO 2023 unit-of-measure type-site.
🇺🇸 United States · Earthwork
Newark Earthworks
Hopewell culture 100 BCE–500 CE · Hopewell (Adena descended, Algonquian? cohort)
Hopewell giant geometric enclosures marking 18.6-yr lunar cycle.
🇺🇸 United States · Earthwork
Poverty Point (Monumental Earthworks of Poverty Point)
Late Archaic 1700–1100 BCE (peak 1500–1200 BCE) · Poverty Point culture
Late Archaic earthwork complex (1700–1100 BCE) with six concentric C-shaped ridges (1.2 km outer diameter) and six mounds, including 22 m-high Mound A – one of largest Archaic earthworks in North…
🇺🇸 United States · Earthwork
Fort Ancient Earthworks
Hopewell 1–450 CE · Hopewell tradition
Largest hilltop enclosure: 40 ha with 67 gateways, Hopewell 1–450 CE, UNESCO 2023.
🇺🇸 United States · Earthwork
Seip Earthworks
Hopewell 1–500 CE · Hopewell tradition
121-acre Hopewell circle-square with 335 m Great Circle and Seip-Pricer mound, UNESCO 2023.
🇺🇸 United States · Earthwork
High Bank Works
Hopewell Middle Woodland 100–400 CE · Hopewell tradition
Circle-octagon pair 320 m circle, UNESCO 2023.