The Mitchell Springs Ruin Group south of Cortez has been listed in the State Register of Historic Properties, according to the Colorado Historical Society.

The prehistoric community was occupied from at least A.D. 800 in the mid-13th century. It may yield important discoveries relating to social history, agriculture, commerce, and community planning and development.

Although much has been backfilled to preserve and protect the resources, the site contains a range of architectural styles associated with all three Pueblo periods.

Two significant features include an unusually large kiva and a unique D-shaped tri-wall structure.

Mitchell Springs Ruin Group also played a major role in the development of the Prudden "unit pueblo" concept, a basic architectural form for the Ancestral Puebloan people.

For the past 10 years, Don Dove, owner of the property, has allowed archaeological field schools from Arizona colleges to participate in testing programs at the property.

The State Register is the official list of cultural resources worthy of preservation within Colorado.The program is administered by the Office of Archaeology and Historic Preservation at the Colorado Historical Society.