Aztec Ruins National Monument

The ruins at Aztec show architectural styles of both the Chaco and Mesa Verde cultures. The Aztec West ruin built between A.D. 1110 and 1125 used Chacoan building style (for instance, T-shaped doorways). Aztec West ruin also had minor additions from a later period from A. D. 1225 and 1252. This later phase of construction used masonry styles similar to the Mesa Verdeans. Rocks and building material derived from local Cretaceous-age sandstone along the Animas River valley were used in construction (Source: Corbett, 1962).