🇺🇸 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 · Earthwork
Troyville Earthworks
Woodland Troyville culture 400–700 CE peak (with Baytown 100 BCE–400 CE foundations) · Baytown / Troyville-Coles Creek (Woodland to early Mississippian)
Nine-mound complex at Jonesville where 21st Louisiana's tallest pre-Columbian mound (Great Mound, 82 ft) stood until levee leveling. Baytown-Troyville-Coles Creek sequence with plaza and embankment.
🇺🇸 United States · Earthwork
Bynum Mounds
Middle Woodland Miller culture Hopewell horizon 100 BCE–100 CE · Miller (Hopewell)
Six mounds at Natchez Trace Milepost 232.4 including large flat-topped Mound A and conical burial Mound B (10 ft high) with crematory basin and greenstone artifacts.
🇺🇸 United States · Earthwork
Plum Bayou Mounds
Late Woodland Plum Bayou 650–1050 CE (Baytown-Coles Creek to Mississippian transition) · Plum Bayou (Baytown/Coles Creek, Late Woodland Arkansas)
Premier Late Woodland platform mound center: 18 mounds (tallest Mound A 12 m) enclosing 16 ha plaza with embankment ditch and astronomical causeway aligned to 1-degree solar solstice.
🇺🇸 United States · Earthwork
Etowah Indian Mounds
Mississippian, Etowah phase 1000–1550 CE · Mississippian (Muscogean ancestors)
19-m Mississippian Temple mound with copper falcon plates and marble effigies.
🇺🇸 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
Pharr Mounds
Middle Woodland Miller culture contemporary with Hopewell 1–400 CE · Miller (Hopewell-influenced eastern Woodland); Hopewell
Eight low dome mounds (2–6 ft high) at Natchez Trace Milepost 286.7, best-preserved Middle Woodland mound group in northeast Mississippi.
🇺🇸 United States · Earthwork
Owl Creek Mounds
Late Woodland to Mississippian 800–1200 CE · Late Woodland to Mississippian (Miller to Mississippian transition)
Five platform mounds (6–12 ft high) enclosing rectangular plaza 100×60 m at Owl Creek, Natchez Trace MP 243.
🇺🇸 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
Shrum Mound
Early Woodland Adena to Early Hopewell transition · Adena
Adena conical mound (20 ft/6 m high, 100 ft/30 m diameter) preserved in Campbell Park, Columbus — one of few surviving mounds in Ohio's capital city.
🇺🇸 United States · Archaeological wonder
Chaco Culture National Historical Park
Pueblo II–III 850–1250 CE (Chacoan fluorescence 1020–1140) · Ancestral Puebloan (Anasazi) / Chacoan
Chacoan canyon with 15 monumental Great Houses (Pueblo Bonito 650 rooms, 35 kivas) and engineered roads, built 850–1150 CE by Ancestral Puebloans as ritual and trade center for San Juan Basin,…
🇺🇸 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 · Ancient village
Mesa Verde Cliff Dwellings
Pueblo I–III (600–1300 CE) · Ancestral Puebloan (Anasazi)
Ancestral Puebloan cliff dwellings (600–1300 CE) with 600 sites including Cliff Palace (150 rooms, 23 kivas) under sandstone alcoves, transitioning from pithouses to masonry pueblos before…
🇺🇸 United States · Buried city
Cahokia Mounds
Emergent Mississippian to Stirling phase · Mississippian (Illinoian)
Largest Mississippian centre (650–1400 CE) with 120 mounds including Monks Mound (30 m, 1000x700 ft base, largest earthen platform north of Mexico).
🇺🇸 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
Kolomoki Mounds Historic Park
Swift Creek–Weeden Island 350–750 CE · Swift Creek – Weeden Island
Woodland Mound A 17 m, Swift Creek 350–750 CE.
🇺🇸 United States · Ancient village
Pueblo Bonito (Chaco Canyon)
Pueblo II–III · Ancestral Puebloan / Chacoan
Greatest great house of Chaco: D-shaped 800-room complex with 32 kivas, planned in stages 850–1150 CE, aligned to cardinal directions and Chacoan road system radiating 60 km.
🇺🇸 United States · Earthwork
Angel Mounds State Historic Site
Mississippian 1000–1450 CE · Mississippian (Angel phase)
42 ha Mississippian walled town 1000–1450 CE.
🇺🇸 United States · Earthwork
Tremper Mound and Earthwork
Hopewell 100–500 CE · Hopewell tradition
Effigy mound with 136 portrait pipes, Hopewell 100–300 CE.
🇺🇸 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
Fort Hill Earthwork and Nature Preserve
Hopewell Middle Woodland 100–400 CE · Hopewell tradition
14.6 ha hilltop enclosure 2.4 km wall, 33 gateways.
🇺🇸 United States · Archaeological wonder
Hovenweep National Monument
Pueblo III 1200–1300 CE · Ancestral Puebloan
Six Pueblo tower villages 1200–1300 CE, Square Tower.