Casa Grande Ruins National Monument
Casa Grande · Great House of Casa Grande
Classic Hohokam 1150–1450 CE (Sedentary to Classic transition)·Hohokam (Ancestral Sonoran Desert, ancestors of O’odham)·🇺🇸 Arizona, United States
About
About Casa Grande Ruins National Monument
Ancestral Sonoran Desert four-story Great House (18 m × 13 m, 4 storeys, 11 rooms, caliche clay walls 1 m thick, internal loopholes) – largest known Hohokam structure, preserved under 1932 modern steel shelter (the ‘great umbrella’ by Frederick Law Olmsted Jr.). Part of 15 ha compound with ballcourt and platform mounds among Gila River irrigation canals (150 km of canals). Occupied 1150–1450 CE by Hohokam (ancestors of Akimel O’odham). First archaeological preserve in US (1892, Harrison).
Why it mattersBenchmark for Hohokam canal irrigation agriculture in desert and caliche construction; test of collapse vs environmental overuse theories.
Open questions
Mysteries & theories
Mysteries
- 01Precise function: elite palace vs solstitial calendar vs communal granary
- 02Cause of abrupt Classic-period abandonment 1450 CE (flood vs salt vs conflict)
Theories
- 01Great House as astronomical observatory: west door aligned equinox, small circular holes mark lunar events
- 02Collapse driven by Gila River salinization and 1330s–1450 drought
Theories are interpretations, not findings. The seal above tells you how much scholarly weight the place carries.
History
How it came to be
- Built
- c.1150–1350 CE; Great House c.1300–1350
- Period
- Classic Hohokam 1150–1450 CE (Sedentary to Classic transition)
- Culture
- Hohokam (Ancestral Sonoran Desert, ancestors of O’odham)
- Purpose
- Elite multifunction building – astronomical observatory (solstice windows), communal storage, elite residence and ritual center
- Excavation
- Partially excavated
c.1150–1350 CE; Great House c.1300–1350
Initial construction
c. 1685 CE
Abandonment
On the ground
Structures & features
32.9975° N · 111.5369° W · 430 m · 3 mapped features
Great House (Casa Grande)
great houseFour-storey caliche Great House
32.9975° N · 111.5369° WBallcourt
ballcourtHohokam ballcourt on north Compound B
32.9982° N · 111.5365° WPlatform Mound
moundCompound A platform mound NE of Great House
32.9980° N · 111.5360° W
Gallery