We traveled to Coolidge, AZ to visit Casa Grande National Monument, which is about 18 miles from our RV park in Casa Grande, AZ. This is the location of a Sonoran Desert farming group of people that dates from around 1000 AD to about 1450. 
These people were impressive builders and left behind a number of building ruins, such as these walls, which form the National Monument.
This is the Great House -- also known as Casa Grande -- for which the area is known. This very large structure is actually 4 stories high and has thick, straight walls built out of a clay substance. Dating from 1350, this shows how strong these buildings were. The roof now over the ruin was erected in 1932 and protects it from the weather.
Orinda shows how accurately these buildings were constructed. These buildings would be pretty impressive today -- imagine how amazing these were in 1350.
These people actually farmed the area using canal systems to irrigate the fields. Amazingly, these huge canal fields were dug by hand and managed for centuries.
This sophisticated culture lasted until about 1450 when the city was abandoned. Some folks believe that there were severe floods which destroyed the canals and fields. In any event, they left behind some amazing feats of engineering. 
We really enjoyed our visit to Casa Grande Ruins and the desert the surrounded it. Well worth a stop if you are in the area!
