Xochicalco: Mexico's Most Underappreciated Archaeological Site?

Our adventure today takes us to western Morelos, in Mexico, where we will explore one of the most standout archaeological sites of the epiclassic period in Mesoamerica, Xochicalco. This exceptionally well-preserved city flourished between about 650 and 900 CE, at a critical juncture in pre-Columbian history, when major city-states were failing one after another. We are going to delve into the question of why Xochicalco thrived when other cities did not. We'll get a close look at what makes Xochicalco unique, its extraordinary fusion of cultural elements from diverse Mesoamerican traditions, including Teotihuacan, Maya, Zapotec, and other regional styles. And we will examine its most famous temple, which some say depicts a great flood that destroyed the world, but it's actually cooler than that. This region of the country is a tropical dry forest, locally known as Selva Baja, which supports all sorts of endemic species of flora and fauna unique to Mexico. The area also has obsidian, which was a crucial material for tool production and long-distance trade for Xochicalco. The geographic isolation of Xochicalco on hilltops, in a region of difficult access, has paradoxically served as one of the primary factors in the site's exceptional preservation. The settlement perches atop a series of natural hills. The valley below the city was used for agriculture to feed the population, and the hilltop location provided exceptional defense advantages and spectacular vistas for their sacred ceremonies. The site museum sits at the entrance, so we got a taste of this ancient culture there first. It contains a substantial collection of artifacts recovered during excavations. Numerous sculpted stone monuments have been recovered. They represent a synthesis of artistic traditions. You'll note similarities with styles from Teotihuacan, the Maya, and the Zapotec. Some monuments appear to represent individual portraits. The glyphs apparently record place names, possibly indicating political associations between Xochicalco and other settlements, or places that offered tribute to the Xochicalcan state. Some scholars have proposed that the scribes of Xochicalco experimented with synthesizing elements from different writing systems into a unified system that would later influence the development of standardized glyph usage that became common from the 13th century onward in Mesoamerica. The name Xochicalco derives from the Nahuatl language and translates to, in the house of flowers. Flowers held spiritual and symbolic meaning in Mesoamerican cosmology, representing fertility. These slabs came from the ramp of animals on site, which I'll show you later. They are a visual documentation of the region's fauna. They suggest that the biodiversity of the area was relevant to Xochicalcan peoples, not only because they hunted these animals for food, but they were part of how the people conceptualized the sacred landscape they belonged to. Even beyond the ramp of animals, various fauna appear throughout the city's decorative program. Limestone sculptures of felines, such as pumas, with elaborate headdresses or iconographic elements appear. The warrior animal associations suggest that different animal species may have been symbols of warrior groups or military organizations within the city. Representations of jaguars, eagles, and other predatory animals were part of Mesoamerican warfare symbolism. Depictions of serpents in various forms appear often. The snake's form was a fundamental cosmic symbol associated with water and earth. Representations of birds, including hummingbirds, macaws, and owls, appear in various contexts. They had meanings related to the celestial realms. Numerous clay censors, incense burners, and other ritual paraphernalia have been found here too, which were used in household religious practices. They frequently bear representations of deities, particularly Tlaloc, with his characteristic googly eyes. Ceramics show that some were made locally and some were imported. Obsidian was not made simply for utilitarian tool production. Obsidian blades and ornaments were luxury items associated with elite status. And likely formed important components of trade partnerships and diplomatic gift exchanges. Xochicalco is built on three levels. And that's not just because of the natural topography. It is a deliberate hierarchical tripartite organization. The lowest level, encircled by defensive walls, contains primarily residential buildings for the general population and skilled artisans. The intermediate level has a major plaza, more residential structures, the largest of three ball courts at the site, and a palace complex. The highest level has the most important temples and monumental buildings that were likely reserved exclusively for the ruling elite and religious specialists. This vertical stratification was achieved through extraordinary engineering efforts. The workers had to construct massive terraces and retaining walls to create level surfaces. And there are complex systems of staircases, ramps, and causeways linking the different levels. People lived here as far back as 200 BCE. But Xochicalco did not become a major urban center until the Epiclassic period, beginning around 650 CE, when nearly all the standing architecture visible at the site today was constructed. The reason it took so long is probably because of the catastrophic eruption of Mount Xitle, not far from here, which occurred sometime between 50 and 350 CE. It rendered the area inhospitable for a long time. And most of the population fled north toward Teotihuacan. Maybe that had something to do with Teotihuacan's population explosion. It was the Omeka-Chicalanca people, whom I introduced you to in the last episode, who founded Xochicalco as an urban center around 650. The plaza of the Stela of the Two Glyphs was probably the city's original ceremonial center. The plaza features stunning panoramic views of the surrounding valleys, particularly southward and westward, and likely served as an ideal location for observing celestial events rising over the eastern hills. Ancient roads leading from the valley floor below to this plaza suggest that it may have been accessible to residents rather than restricted to elite and priestly classes alone, indicating a degree of public participation in ceremonial life. The central feature of this plaza is the famous Stela of the Two Glyphs, this one being a replica. The original stela is on display in the National Museum of Anthropology in Mexico City. The stela displays two composite glyphs on its front face that have been interpreted as calendar dates, reading Ten-Reed and Nine-Reptile-Eye. The Nine-Reptile-Eye glyph appears repeated on the Temple of the Feathered Serpent and is thought to represent Xochicalco's emblem glyph. It's been proposed that the stela was erected in the calendar year Ten-Reed specifically to honor the Feathered Serpent god and may commemorate the founding of the plaza or the city itself. The Great Pyramid, Structure E, is the largest building in Xochicalco and was dedicated to Tlaloc, the god of rain and water. At the apex stand the remains of what was likely a substantial temple structure. The intermediate level of Xochicalco, called the Plaza of the Market Ensemble, was a marketplace where goods were exchanged and seems to have been commercially important on an inter-regional level. A substantial proportion of the urban population was engaged in craft production and long-distance trade. Remember those slabs featuring animals I showed you in the site museum? This is their original location. Known as the Ramp of Animals, there were 271 individual stone slabs found here, each engraved with detailed artistic representations of fauna. Archaeological evidence suggests that many of these decorated stones originated from other locations within the city and were collected and placed along the ramp during later modifications to the complex. The causeway leading from the market to the southern ballcourt is lined by an impressive series of 21 calendar altars, each recording specific months and ceremonial days of the ritual year. These calendar altars would have guided ceremonial processions. During the Epiclassic period, between 650 and 900, Xochicalco's population reached an estimated 15,000 to 20,000 inhabitants, making it one of the largest and most important centers in central Mexico at that time. This era witnessed the decline and collapse of the great classic period city-states including Teotihuacan, Monte Oban, Palenque and Tikal. In fact, the terminal decline of Teotihuacan created conditions that enabled Xochicalco to ascend to prominence. Some scholars have speculated that Xochicalco may have even played a direct role in hastening the decline of Teotihuacan, either through military or economic competition. Perhaps the most remarkable technological achievement at Xochicalco is the Astronomical Observatory, an artificially modified cave complex that demonstrates sophisticated understanding of solar movements and celestial mechanics. The cave was originally used for quarrying limestone, but in the Epiclassic period, city engineers transformed this quarried cave into a precise astronomical observation instrument. The observatory was accessible through restricted passages with defended portals. The cavern was plastered with stucco and painted in red, yellow and black pigments, with a man-made shaft constructed through overlying rock to connect the interior chamber with the surface above. The observatory's function centers on the precise days when the sun passes directly overhead at noon. At Xochicalco's latitude, the sun reaches zenith positions on two specific dates, around May 14-15 and July 28-29, when the sun's direct rays beam down through the carefully calculated shaft, creating a luminous projection on the chamber floor. The interval between the two zenith positions, exactly 260 days, is the length of the sacred Mesoamerican calendar. The main plaza is the civic and ceremonial heart of Xochicalco. Sitting approximately 100 meters above the main entrance to the city, the plaza is accessible only through two defended porticos, which tells us that this place was restricted. The Temple of the Feathered Serpent is the most visually impressive monumental structure at Xochicalco. It's oriented along an east-west axis, giving it cosmological implications. The sculptural style of the Temple of the Feathered Serpent demonstrates clear influences from Teotihuacan, most notably in the talud-tablero architectural form, and the overall artistic program represents a unique synthesis of Teotihuacan, Maya and local Xochicalcan artistic traditions. Religion at Xochicalco, like at Teotihuacan, centered on the worship of two fundamental deities, representing complementary cosmic principles, Tlaloc, the rain god, associated with water, fertility, and sustenance, and the Feathered Serpent, associated with wind, breath, and cosmic movement. These deities form the basis of a cosmological system of opposed, yet complementary, dualism, with associated pairs of contraries linked to each deity. While presumably any visitor of the city could participate in the rain-related ceremonies associated with Tlaloc, in the Plaza of the Stela of the Two Glyphs, the Feathered Serpent's religious status was more restricted. Some scholars have proposed that Xochicalco may represent the place where it was believed the Feathered Serpent deity first became humanized, subsequently influencing later Mesoamerican religious concepts during the Toltec and Mexica periods. We're here at the top of Xochicalco, at probably the most iconic building in the whole city, alright, and this is the temple of the Feathered Serpent, Quetzalcoatl. And if you look, you'll see a serpent. If you notice in the body, there are representations of seashells and other aspects of water, so it's probably symbolizing water. But also on here, you'll see people. Many of them look like Maya people and others, some of them have like cranial deformations like the Maya used to practice, but they're people from different places that are represented here and they're speaking and glyphs are coming out of their mouth. And we believe that this temple was built to commemorate an important event that's documented elsewhere in 743 when priests and rulers and warriors from other places came here to engage in science. They wanted to discuss science and astronomy and the calendars and try to harmonize them so that all the people were engaging in this practice together. They're unifying their methods of astronomical observance. The scholars of the ancient Mesoamerican world coming here at that time and we believe that this temple was built to commemorate this event. This is a serpent or something about to swallow a circle that's quartered. We think that's the sun and that this is representing perhaps an eclipse. The calendar systems referenced in the Temple of the Feathered Serpent, the Stela of the Two Glyphs, and the Observatory represent a combination of different chronological traditions, suggesting that the intellectuals of Xochicalco attempted to coordinate at least three different Mesoamerican calendar cycles. The gathering of priests in 743 to observe a solar eclipse and synchronize their calendrical systems cemented Xochicalco's reputation as an intellectual center of considerable sophistication. You never see the interior. You always see the outside. I didn't know it was hollow. Look at that. So cool. Two major architectural complexes dominate the space around the main plaza. They contained residential, administrative, and ceremonial buildings. The ruler and his immediate family occupied the eastern residential areas of the Acropolis, which provided commanding views overlooking the main plaza and the broader city below. The thick stone walls of the Acropolis structures maintained steady temperatures, staying warm during cooler seasons and providing refuge from intense heat during summer months. Granaries that held mostly maize occupy the northwestern corner, consisting of small rectangular spaces with no obvious conventional entrances except possibly extremely narrow openings inadequate for adults, suggesting roof-level hatch access that would have protected stored grain from rodent and human pilferage. Two long narrow rooms built onto the Acropolis's exterior southern wall, subdivided into smaller compartments, are believed to have functioned as workshops where the rulers retained artisans crafted luxury goods for elite use. Despite Xochicalco's hilltop location, the people here built an impressive water management infrastructure, including large rainwater cisterns and channeling systems. It demonstrates the sophisticated engineering and hydrological knowledge of the ancient Mesoamericans. In the early 10th century, Xochicalco experienced a rapid, violent destruction. One theory is that there was an internal popular uprising or rebellion led by lower classes against the elites, such as what happened at Teotihuacan earlier. An alternative hypothesis proposes that Xochicalco was conquered by an unidentified external group from elsewhere in Mesoamerica. Yet another theory proposes a breakdown within the political confederation that Xochicalco headed, with affiliated settlements withdrawing their support and contributing to the city's loss of power. All of these scenarios fit, to some degree, the archaeological evidence. Despite its ultimate demise, Xochicalco's cultural and intellectual achievements appear to have exercised significant influence on subsequent Mesoamerican civilizations, including the Toltec and later the Mexica-Aztec empires. For this reason, knowing about this magnificent city is a must for anyone interested in understanding the history of Mesoamerica. In our next episode, we are traveling to the ruins of Mexico's greatest ancient city, Teotihuacan. I will show you the major monuments, tell you the latest information we have about them, and show you lesser known parts of the city too, which might amaze you just as much. Stay tuned, and don't forget to subscribe.