Teopantecuanitlan is an archaeological site in the Mexican state of Guerrero that represents an unexpectedly early development of complex society for the region. The site dates to the Early to Middle Formative Periods, with the archaeological evidence indicating that some kind of connection existed between Teopantecuanitlan and the Olmec heartland of the Gulf Coast. Prior to the discovery of Teopantecuanitlan in the early 1980s, little was known about the region's sociocultural development and organization during the Formative period. Location Teopantecuanitlan is located in the state of Guerrero, about 20 km in the southwesterly direction from the town of Copalillo. The nearest village is Tlalcozotitlan. It is situated at the convergence of the Amacuzac and Balsas rivers, and five miles (8 km) from where the Amacuzac flows into the Mezcala River, providing an environment for trade and travel. Teopantecuanitlan occupies some 1.6 to 2 km² (500 acres), and is situated at the foot of a sharp hill which rises 200 m above the site. Teopantecuanitlan was a center for a region that included Oxtotitlán, Juxtlahuaca, Xochipala, Zumpango del Río, and Chilpancingo. Art and architecture Teopantecuanitlan was occupied from 1400 to 500 BCE, a period which is generally divided into four phases, peaking in population and complexity during Phase II, between 1000 and 800 BCE. The site’s settlement largely consisted of residential compounds characterized by four structures arranged around a shared courtyard or plaza. The structures themselves were made of perishable materials built over stone basal foundations. Imported shell and obsidian artifacts, as well as Olmec-influenced ceramic wares, have been found in association with and inside the residential groups. These artifacts provide material evidence that the Teopantecuanitlan community was a part of an interregional trade network that linked the Gulf Coast with the highlands of Central Mexico. Mezcala culture type artifacts were found in the Teopantecuanitlan area. To the north of the Sunken Patio, clay sculptures were found. These were the oldest sculptures on the site. Some similarities are found between them and the monuments at Ojo de Agua, Chiapas, dated to 1200-1100 BC. Sunken Patio In addition to the residential areas, Teopantecuanitlan is notable for its monumental architecture, art, and agricultural terraces, in particular one of the first civil-ceremonial structures in all of Mesoamerica, El Recinto ("the enclosure"), also known as the Sunken Patio, constructed during Phase II (between 1000 and 800 BCE). The Sunken Patio is so-named because it is