🇺🇸 United States · Geoglyph
Topock Maze (Mystic Maze) Geoglyphs
Late Prehistoric (Patayan) to Historic · Mojave (Aha Makav) / Quechan
18-acre windrow maze (800–1200 CE) in Mojave Valley — 600-m herringbone pale strips.
🇺🇸 United States · Geoglyph
Bouse Northern Wash Intaglios (La Posa Plain Extension)
Late Prehistoric (Patayan II–III) · Patayan / Hakataya (Yuman)
9+ Patayan intaglios (880 BP–1500 CE) on La Posa Plain north of Bouse — Colorado River style.
🇺🇸 United States · Geoglyph
Bouse Fisherman Intaglio (Fisherman Geoglyph)
Late Prehistoric (Patayan) · Yuman (Mojave/Quechan)
9-m Fisherman intaglio (900–1200 CE) on Plomosa piedmont — spearman with fish and sun.
🇺🇸 United States · Earthwork
Moorehead Circle at Fort Ancient
Middle Woodland Hopewell (c.100 BCE–250 CE) with Fort Ancient reuse · Hopewell → Fort Ancient
Outer-embankment timber circle 60 m diameter discovered 2007 by magnetometry inside Fort Ancient Hilltop Enclosure (Hopewell 100 BCE–500 CE, later Fort Ancient reuse).
🇺🇸 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
Effigy Mounds National Monument
Late Woodland 500–1200 CE, effigies c.700–1100 CE · Late Woodland (Ancestral Ioway/Ho-Chunk?)
31 bear-and-bird effigy mounds marching on Mississippi bluff.
🇺🇸 United States · Earthwork
Alligator Mound
Late Woodland / Fort Ancient 800–1200 CE · Fort Ancient (Late Woodland)
Effigy mound 205 ft/62 m long, 4–6 ft high, head oriented SW tail NE, depicting an opossum/underwater panther effigy on bluff south of Granville. Listed NRHP 1971.
🇺🇸 United States · Geoglyph
Blythe Intaglios
Late Prehistoric 1000–1500 CE (OSL), possibility Protohistoric · Mojave/Quechan; Patayan culture
Mojave giant desert figures: 50-m human intaglios above Colorado River.
🇺🇸 United States · Earthwork
Great Serpent Mound
Disputed: either Adena 320 BCE–200 CE or Fort Ancient 1070–1200 CE (latest C14 favors Fort Ancient 1120 CE) · Adena culture or Fort Ancient culture
Quarter-mile (411 m) effigy mound in shape of serpent with oval head swallowing an egg, 3 ft high, coiled tail atop meteor-crater plateau above Ohio Brush Creek, largest surviving effigy mound in…
🇺🇸 United States · Earthwork
High Bank Works
Hopewell Middle Woodland 100–400 CE · Hopewell tradition
Circle-octagon pair 320 m circle, UNESCO 2023.
🇺🇸 United States · Earthwork
Marksville State Historic Site
Marksville 0–400 CE · Marksville culture
Semicircular enclosure 530 m wall, Marksville Southern Hopewell 0–400 CE.