Casa Grande Ruins

No, we did not ruin the city of Casa Grande.  The "Casa Grande Ruins" is a National Monument located in Coolidge (named after "Silent Cal") about 20 miles from Casa Grande.  It is the first archaeological reserve in the country, created in 1892.  It became a National monument in 1918. 

The Monument preserves the site once occupied by an ancient farming community of the Hohokam people who were in the area about 300 AD.  The people survived here until the 1400s.  Upon finding the deserted site, early Spanish explores named it Casa Grande, the "big house." 

The people developed a vast system of canals to irrigate their crops from a nearby Gila river.  They grew many vegetables including corn and squash and cultivated cotton from which they made their clothes.  They made pottery and were involved in trade with other communities.


The primary structure on the site is a three story structure built about 1350 AD from caliche.  Caliche is the hard subsoil under the desert composed of limestone (calcium carbonate).  When mixed with clay and  sand, it dries into a concrete like mixture.  The structure is now covered to protect it from the weather:

The caliche mud was piled layer upon layer creating walls four feet thick at the base.  Logs from distant trees were used to form the ceiling and the floors (3 story high).   This is but one building on the walled site, but it is by far the largest and probably the most important to its inhabitants. 

The interior of the building has several rooms.

The building like many ancient structures is aligned with the sun and moon.  Its walls face the four point of the compass.  A hole in the west wall aligns with the sun setting at summer solstice.  Other holes in the wall align with the sun and moon at certain times of the year. 

This big house is but one of many structures which stood in this area.  Other structures were significantly smaller.