An ancient scorpion-shaped mound in Mexico was built between 600 and 1100 AD, according to archaeologists from the University of Texas at Austin and Mexico’s National Institute of Anthropology and History (INAH).
The team named the stone-and-earth site the Scorpion Mound. The site is located in the arid Tehuacan Valley in Puebla state, about 260 kilometers southeast of Mexico City. The complex may have served as both a ceremonial center and an astronomical observatory for tracking the Sun at the summer and winter solstices.
The Scorpion Mound is part of a larger ceremonial and public complex covering roughly 9 hectares. It contains at least 12 other mounds connected by prehistoric irrigation canals, Arkeonews reports. Those canals are part of one of the largest and oldest water-management systems, which once supported around 100 square kilometers of agricultural land.
What Did the Researchers Report?
Drone photography and GPS mapping confirmed the mound is not a random pile of stones but a carefully constructed complex.
The mound, approximately 62.5 meters long and 80 centimeters high, symbolically represents the scorpion deity Tlauizcalpantecuhtli, associated with Venus, rain, and fertility.
When viewed from above, the silhouette of a scorpion is unmistakable: the body, two elongated pincers, and a curved tail. Archaeologist James A. Neely, the lead author of the study, says mounds associated with idol worship are common in parts of North America but rare in this region. He adds that this mound represents a unique blend of “astronomical knowledge, ritual practice, and local agricultural traditions.”
While mapping the complex, researchers found that the direction from the scorpion’s stinger (the tip of the tail) to the left pincer forms a 65-degree angle to the east-northeast. That angle points to the position on the horizon where the Sun rises on the summer solstice. During the winter solstice, the sunset aligns with the scorpion’s tail when viewed from the left pincer.
That geometry suggests the mound was used as a solar calendar to mark the changing seasons. That knowledge was vital in the semi-arid valley. “For ancient farmers, observing the solstices was not a luxury. It was essential for survival,” Neely explained.
The summer solstice marked, among other things, the beginning of the rainy season, signaling the right time for planting corn and other crops. The winter solstice marked the end of the season—a time for ritual offerings and ceremonies of gratitude.
During excavations, archaeologists discovered ceramic vessels, incense burners, and fragments of figurines that indicated ancient ritual traditions.
Connection to the Cosmos
The scorpion symbol held deep cosmic significance for the ancient peoples of Mexico. In Aztec mythology, the creature was associated with Venus as the Morning Star—a celestial force tied to water, fertility, and renewal. This imagery also appears in Cacaxtla, a nearby ceremonial center known for vivid frescoes depicting Venus and the scorpion.
Unlike the monuments in cities like Chichen Itza or Monte Albán, the Scorpion Mound reflects the astronomical knowledge of rural farmers rather than the elite. Its builders were likely villagers whose daily lives depended on the land and the sky.
The findings of the study were published in the journal Ancient Mesoamerica.
