Los Guachimontones (also spelled "Huachimontones") is an archaeological site dating from pre-colombian times. It is located near the Teuchitlán in Jalisco about an hour west of Guadalajara. It is the major site of the so-called Teuchitlan tradition, a complex society that existed from as early as 300 BCE until perhaps 900 CE.
The dominant features at los Guachimontones are circular stepped pyramids in the middle of circular building complexes. The 60-foot (18 m) tall pyramid at Circle 2 has 13 high steps leading to an upper level, which was then topped with another 4 high steps. A post hole was located at the very highest level, most likely for volador ceremonies. The pyramids may also have supported small temples.
Sunken circular plazas surround each pyramid and a series of smaller mounds surround the plazas. On top of the mounds are platforms that once supported wooden buildings made of wood and clay.
The site has a total of 10 circular complexes, four rectangular plazas, two ballcourts.
The excavation of the site has been the focus of archaeologists from the Colegio de Michoacán under the direction of U.S. archaeologist Phil Weigand and his wife Celia Garcia de Weigand. A large project has been underway at the site since 1998.
UNESCO has added the whole region, including the nearby tequila distilleries, to its World Heritage List. Due to heavy looting, the site was also included on the 2008 World Monuments Watch list of 100 Most Endangered Sites.
from Wikipedia: en.wikipedia.org/wiki/Guachimontones