Los Guachimontones is the largest Late Formative to Classic period (300 BCE to 450/500 CE) pre-Columbian archaeological site in the state of Jalisco.

During her travels, near the town of San Marcos Breton documented a mound in the process of being destroyed that contained several burials, hollow ceramic figures, and shell ornaments.

Breton took three photographs of the site, created two sketch maps, and collected a number of obsidian artifacts from a Postclassic workshop.

Following shortly after Breton, anthropologist Carl Lumholtz journeyed through the Tequila Valleys as part of his travels south from Phoenix, Arizona through the Sierra Madre Occidental to Michoacán.

While Lumholtz did not record a visit to Los Guachimontones itself, did acquire ceramic vessels from the nearby town of Estanzuela to the southeast of Teuchitlán.

[11]: 160  Of some importance are the photos Lumholtz took of Laguna Magdalena showing the extent of some of its shoreline before the lake was largely drained in the 1930s to create arable land.

[12] Laguna Magdalena would have provided important lacustrine resources to the Teuchitlán culture in the form of fish, reeds, lake fowl, and other goods.

Despite archaeological work conducted in the Magdalena Lake Basin by Jose Corona Nunez in the 1950s[14] and Stanley Long in the 1960s[15] at the sites of El Arenal and San Sebastian, the guachimontón went unrecognized.

[16][17] Until Weigand's publication, other Mesoamerican academics characterized West Mexico as a region made of small hamlets with no significant contributions until the Postclassic period and rise of the Kingdom of Tzintzuntzan in present-day Michoacán.

Weigand continued working in the Tequila Valleys region for three decades documenting dozens of Teuchitlán Culture sites with guachimontones, Mesoamerican ballcourts, house mounds, and shaft and chamber tombs.

Heredia continues to conduct research at the site with a focus on analyzing the substantial collection of artifacts recovered from Weigand's excavations.

[29] A typical guachimontón (colloquially called a circle in both English and Spanish) consists of four basic architectural features: the patio, the banquette, the altar, and the platforms.

Variation in guachimonton form and orientation exists throughout the Tequila Valleys that makes understanding the structures, their meaning, and their use somewhat difficult to interpret.

Circle 6 is notable for containing several secondary burials within its altar, possibly part of a place-making ritual involving important ancestors.

The Late Formative (or Tequila II phase) dates from 300 to 100 BCE This period is characterized by the construction of many of the larger monumental buildings like Circle 1 and Ball Court 1.

[1] Settlement survey and ceramic evidence suggests a growing population during this period as people settled near the center or made more permanent house platforms.

[34] Secondary burials were deposited at the smaller Circle 6, possibly part of a place-making activity involving the remains of important ancestors.

[31] The Early Classic (or Tequila III phase) dates from 100 BCE to 200 CE This period is characterized by the continuing construction of guachimontones and ball courts, like Circles 2 and 3.

[34] Late Classic (or Tequila IV phase) dates from 200 to 450/500 CE During this period, there is a drop in population levels at the site and currently the cause is uncertain.

[1] Instead, “ranchos,” or small house groups, located on top of or nearby the abandoned ceremonial buildings, characterize the Postclassic period.

Lopez Mestas argued the primary mechanism of power that chiefs relied upon was their ability to engage in trade for exotic or prestigious goods, like jadeite and shell, from outside of the Tequila Valleys.

Lopez Mestas suggests that elites would try to convince commoners to donate artisan goods or domestic surplus to increase chiefly wealth and status.

[41] He suggested a model in which Teuchitlán Culture centers were ruled by corporate groups composed of multiple lineages, clans, or elite families.

Christopher Witmore[47] interprets the form of the guachimonton, with the altar in the center and platforms arranged around the patio space, to represent the sun.

The ceramic models without a pole in their center often depict the spaces as a hub of activities from marriage ceremonies, to food preparation, to music making and dancing, and even warfare.

Oliver Flores[50] has proposed that Altar C2 contains geometric alignments that make up the structure of a functional 52-year Mesoamerican calendar system.

Radiocarbon and ceramic evidence suggest a construction date between 80 and 220 CE[1] Circle 3 is also unique for a nearby small plaza space just to the south of the structure.

Circle 6's importance continued into the Epiclassic with a number of burials found within the patio space and several offerings arranged in a line facing one platform.

[1] A small platform is located in the north end of the playing space of Ball Court 2 that dates to the Epiclassic and Postclassic periods.

However, excavations at Los Guachimontones have recovered figurines in non-mortuary contexts in sufficient quantities to question the “shaft tomb figure” label.