Chaco Canyon: Mystery and Intrigue

Chaco Canyon during the years 850-1150 AD is perhaps the most fascinating chapter in Southwest USA history. The ultimate fate of the mysterious, “disappeared” Anasazi (Ancestral Puebloan) Indians intrigues social scientists, archaeologists, and visitors to this day. Their colossal achievements can be observed in many places, including the striking cliff dwellings of Mesa Verde. But the crest of the Anasazi wave was Chaco Canyon, a shallow, windswept wash in northwest New Mexico. Here in Chaco Canyon, 1,000 years ago, strange and unexplained events unfolded.

the chaco culture national historic park welcome sign

Chaco Culture National Historic Park

Despite the remote charm of Chaco Canyon’s enigmatic landform, its brutally long winter season, ultra-brief growing season, and scare rains make it an unlikely location for the Capitol of Anasazi (Ancestral Puebloan) culture. Utilizing masonry methods never before seen in North America, they built huge, complex stone structures (multi-story Great Houses) consisting of numerous rooms much bigger than any the Anasazi had formerly constructed.

These structures were conceived, planned, and built from scratch, in stark contrast to their previous system of modifying or adding on to pre-existing stone structures. Although each Great House is distinct, they all share architectural commonalities that identify them as uniquely Chacoan. Advanced astronomical alignments, ingenious agriculture, water control systems, and mysterious mounds of talus and earth surrounded the Great Houses of Chaco. Chaco’s structures were established in a sparse landscape enclosed by spiritual mountains, forested buttes, mesas, and unknowable ritual structures that still have deep spiritual significance for the Anasazi descendants, which include the Hopi, Zuni, and Puebloan tribes.

doorways inside the pueblo bonito great house

Public Architecture

Chaco Canyon’s structures are excellent examples of pre-Columbian “public architecture”, utilizing advanced engineering to create spectacles and serve as gathering points. This facilitated distant trading and commerce and supported short-term populations gathered in Chaco Canyon for these ceremonies and events. Pueblo descendants affirm that Chaco existed as a unique meeting place where individuals and clans assembled (often in Kivas) to experience their events, trade their goods, and participate in ceremonies, customs, and understandings. Was Downtown Chaco the center of a far-flung trading network developed to attract the trade of chocolate, seashells, macaws, copper bells, and other products from far-off lands?

Outliers and Chaco’s Sphere of Influence

Chaco’s impact continued long after it was no longer the center of the Anasazi world, The complexes at Aztec, in the Chuska hills, the cliff dwellings of Mesa Verde, and other centers to the north, south, and west, and throughout the Colorado Plateau, which is roughly the 4-corners region. Eventually, the Anasazi moved away from the Chacoan life and methods, migrated away to new (and previously occupied) locations, restructured their society, and ultimately connected with other tribes and cultures. Numerous Southwest Indian Tribes consider Chaco Canyon as a crucial waypoint in their clans’ spiritual migration paths, respecting Chaco as a spiritual location to be venerated and appreciated.

Anasazi ruins left in Chaco Canyon inspire all those who visit them

The Uniqueness of Chaco Canyon

Chacoans engineered and built impressive works of public architecture which lacked precedent in the ancient North American world, and which stayed unrivaled in size and intricacy up until the development of steel, long after Columbus arrived. This absence of written or preserved records adds to the mystique surrounding Chaco. With the archaeological and anthropological evidence limited to items and structures left, lots of tantalizing clues tease scientists but refuse to fully reveal their secrets.

Human Settlement

The first indication of long-lasting human settlement in Chaco Canyon dates to the 3rd century CE with the building of partly below-ground houses referred to as pithouses, structures which became clustered together to form villages. The fantastic, multi-story Great Houses, like Pueblo Bonito, and constructions, were a giant leap in technology and construction. Chacoans produced strong, tall walls utilizing a variation of the “core-and-veneer” building strategy. Although today these mosaic design veneers are in evidence to visitors, adding a striking charm to these structures, Chacoans used plaster on most exterior and interior walls as soon as construction was complete to protect the delicate mud mortar from water damage and add aesthetic appeal. In addition to natural sandstone tanks, rainwater was captured in wells and dammed locations that trapped the furious torrents of water off the canyon walls when thunderstorms struck.

logs used to build the chaco great houses were transported from great distances

The Chaco “River”

The arroyo (a periodically flowing stream) that sculpted the canyon, Chaco Wash, occasionally flowed with water, but it was likely muddly and saline. To build the Kivas and Great Houses, Chacoans traveled over 80 kilometers to coniferous forests to the south and to the west, felling trees, then peeling and leaving them to dry to decrease weight. Then, by hand across the unforgiving desert, they carried them back to Chaco Canyon. Remember, there is no evidence of the use of wheels or domesticated animals to help with the burden.

the chaco wash arroyo river in flood

Architecture Alignment with Solar and Lunar Events

Key to the structure of the Chacoan world was the practice of aligning structures and roadways with the positions of the sun and moon at key intervals, such as solstices, equinoxes, and lunar alignments. Chacoans imported unique items, birds, and animals by means of trade paths that extended west towards the Gulf of California and south more than 1000 kilometers along the coast of Mexico. Seashells (obviously not native to Chaco Canyon) were utilized as trumpets. Other goods discovered include copper bells, cacao (chocolate!), and the remains of scarlet macaws, which are parrots with lively red, yellow, and blue plumes. With life at Chaco difficult during periods of even typical rains, a prolonged drought would have strained resources and set migration in motion. This is what appears to have occurred in the middle 1100’s.

Ancient Observatories: Chaco Canyon

Chaco Canyon is seventy miles from the closest town and accessible only by axle-busting washboard dirt roadways. Remote? Yes, it is. The Anasazi were nomadic, classic hunter-gatherers. When the first agriculture appeared, and they settled on the Colorado Plateau and begin building and living in small pit houses. Frequently constructed with celestial positioning in mind, they also constructed water-collection systems and were connected to far-flung Chacoan outliers by a substantial network of roadways. It’s not entirely clear why the Anasazi abandoned Chaco Canyon, however, tree ring data indicates extended dry spells, and is one possible explanation. It was around this time that the population in other locations in the area, such as Mesa Verde and the Chuska Mountains, grew in size and significance. Today, modern-day Pueblo individuals trace their roots to Chaco Canyon and consider it a spiritual location.

the sun dagger, used to track lunar and solar events

Public Protections

Chaco Canyon ended up being designated a nationwide historic park in 1980, and was designated a UNESCO World Heritage Website in 1987, placing it among a curated list of safeguarded locations “whose impressive natural and cultural resources form the typical inheritance of all humanity”. Today, approximately eighty thousand people arrive to explore Chaco Canyon each year, the majority of them drawn to see the remains of the excavated Great Houses, which are preserved in a state of “arrested decay”. Chaco Canyon continues to be a primary destination for those with an interest in ancient cultures, especially those interested archeoastronomers.

Evidence of Advanced Astronomy

Proof exists in many forms that the Chacoans were knowlegeable skywatchers, and they had a clear understanding of the cyclic and seasonal patterns of the sun, moon, and stars. Uncontaminated by city lights, Chaco Canyon’s nighttime skies are resplendent with stars and other astronomical phenomenon that are seldom seen from somewhere else. Why did the ancient Anasazi construct such an extravagant destination in so extreme an environment; one with 100-degree summer seasons, freezing subzero winter seasons, and just 9 inches of rain each year?  This remains a mystery to this day.

chaco canyon has harsh, bitter winters

Chaco Culture History

An ancient and magical location, Chaco Canyon is a delicate and crucial piece of pre-Columbian cultural and historic conservation. The Ancient Anasazi were experts in building and construction, and they left behind proof of understanding advanced archeoastronomy. This is evident through the numerous structures lined up to catch the cycles of the sun and moon. The canyon’s 15 complexes include the biggest structures north of Mexico until the 19th century.

Climate Change in the San Juan Basin

The Chacoans and their complex, astronomically-influenced architecture flourished between AD 900 and 1150, most likely ending due to a drastic change in climate that produced a dry spell that lasted perhaps half a century. The grandest of the Great Houses is Pueblo Bonito, a four-story high complex with 650 “rooms”, using up nearly 2 entire acres of land with its girth, its huge scale a sign of the spiritual power of the Great House. Pueblo Bonito sits straight on the East-West line, an axis that matches the equinox sun. Some higher than others, the kivas hosted worshippers, workers, and clan meetings. Some are still standing almost intact, some endure as structure ruins, the park contains upwards of 2,400 recognized archeological sites, and few of them have been completely excavated. Due to the fragile condition of the erosion-prone canyon, some parts of the park are closed to the general public, however much of it can be seen by automobile.

chacoan ruins kiva, as seen from above

Northwest New Mexico

The Anasazi were nomadic hunter-gatherers spread over a large area. By 700 AD they started to collect in settled neighborhoods, of which Chaco Canyon is the grandest example. Extensive building and construction took place throughout Chaco Canyon from 900 to 1100 AD, leading to the construction of several advanced Great House complexes. Pueblo Bonito (implying “pretty town” in Spanish; the initial Anasazi name being unidentified) had more than sex hundred spaces or rooms, many 2 and three-story structures, numerous ritualistic structures called kivas, and an estimated population between 800 and 1,200 individuals.

The Chaco Road Network

Radiating out from the Chaco complex are an enigmatic series of straight lines or roads that extend 10 to twenty miles into the desert, often going nowhere. They transverse mesas (table-top mountains), up and down vertical cliffs, and along routes which are unwise for use by the casual or even motivated tourist. Paul Devereux, a British scholar and author of the so-called “Earth Mysteries” has suggested these lines (and others he has actually studied all over the world) are much better comprehended as markings that represent the spiritual journeys of ancient shamans.

the chaco outlier road network map

Chaco Roads: Ceremonial, Functional, Both?

Checking these roads at ground level, it appears they have been created over multiple centuries, and have been subjected to natural disintegration, making it hard to determine purpose and use. Scientists from the University of Arizona examined tree-ring information to determine the canyon’s wood geographical origins, the first time this dendroprovenance approach has been utilized in the southwestern United States.

Wood Sources

Prior to 1020 AD, the majority of the wood originated from a formerly unacknowledged wood source; the Zuni Mountains, about 75 kilometers to the south of the Chaco Canyon. Christopher Guiterman from the University of Arizona, lead author of the research study, informed CWA (Current World Archaeology), ‘The study reveals the wood was carried to Chaco Canyon from a great distance, without the help of beasts of burden, the wheel, metal tools, or a significant watercourse, and the wood procurement was a vibrant and on-going enterprise. We now see that when products start to show up from the Chuskas, the development and expansion of Chacoan society takes root, and the Chaco we understand today is the consequence of this change.’

The Sun Dagger of Chaco Canyon

High atop the dramatic Fajada Butte at the entryway to Chaco Canyon is the most enigmatic and celebrated of Chaco’s sites. There, a set of spiral petroglyphs pecked into a cliff face behind 3 huge pieces of sandstone rock functions as a sophisticated solar marker. At summer season solstice, a vertical shaft of light pierces the primary spiral precisely at its center. At the winter season solstice, 2 beams of light flawlessly bracket the exact same spiral. Light beams hit the heart of a more diminutive sized spiral on the spring equinox, and also at the fall equinox. This site, now famously called the “Sun Dagger”, was originally interpreted by Anna Sofaer in 1977. After additional, voluminous analysis, Sofaer and her partners and associates published additional information that seemed to reveal that the chiseled spirals might furthermore be tracking the 18.6-year “lunar cycle”. Sadly, it’s no longer possible for anyone to see the Sun Dagger working. In 1989, the huge sandstone rock pieces moved, potentially from accelerated disintegration of the supporting soil due to visitors, and the effect was forever ruined. Today, the site is closed to visitors.

Pueblo Bonito


Pueblo Bonito is one of the most extensively researched and commemorated cultural sites in Chaco Canyon. Planned and built in phases in between 850 AD – 1150 AD by Ancestral Puebloan (Anasazi) individuals, this was structure in Chaco Canyon was the center of the Chacoan world. This empire ultimately covered a large chunk of the contemporary Southwest, consisting of the San Juan Basin of New Mexico, and parts of Colorado, Utah, and Arizona. For over 300 years, Chacoan Culture unified the populations of a large area within its sphere of impact.

The Greatest of the Great Houses

For nearly 300 years between 850-1150, Chaco Canyon, situated in NW New Mexico, was the location of a couple of thousand Anasazi (Ancestral Puebloan) Indians who formed the central nexus of a political, economic, trading, spiritual, and business empire. It included modern-day New Mexico and spread out to include Colorado, Utah, and Arizona. Chaco existed as a ritualistic city and its Great Houses, instead of residential homes (other than perhaps for political or spiritual leaders), were devoted to different functions, possibly storage of grain and other foods items for distribution, and perhaps even as transient lodging for visitors who came for economic, political, business, or ritualistic events. Started around the mid-800’s, by the waning decades of the 1100s, Pueblo Bonito had swelled to over 600 spaces with nearly forty kivas,  2 and one-half acres, and, in some parts, stood greater than 4 stories.

the casa rinconada great kiva, on the north side of chaco canyon
Casa Rinconada: The Greatest of the Great Kivas

From Pit Homes to Great Houses

For hundreds of years, the Anasazi resided in pit homes, partly immersed structures capped with a thatched and rudimentary adobe roofing system sustained by a wood structure. Now a structure made from sandstone blocks, hewn without the benefit of metal tools, held together by simple adobe mortar, was ascending from the dry and windy ground of Chaco Canyon, demonstrating these Anasazi were competent designers,  architects, engineers, and masons. Though the original plaster is long gone, the walls nevertheless stand, while practically all other building and construction has dissolved back into the beautiful earth. The remaining  Pueblos of today, which include the Acoma, Hopi, Taos, and others, remain brilliant reminders of the determination of Chaco’s impact and power that Pueblo Bonito preceded. (Ortiz 1994:69). There are more intriguing reminders of the Chacoan People, unique masonry patterns; room-size racks; “elite” artifacts, such as copper bells, macaws, and shell precious jewelry.

Summary: The Chaco Canyon Story

  • 400 years before Columbus arrived in the new world, a civilization of stunning complexity and remarkable knowledge flourished in a desolate corner of modern day New Mexico called Chaco Canyon. These were the fabled Anasazi.
  • 1000 years go, in this unassuming, shallow canyon, master builders and architects erected massive four story buildings, each with more than 600 rooms, flanked by underground ceremonial chambers called Kivas, some of which are capable of holding 400 people at a time.
  • These stone and timber buildings are constructed with precise solar and lunar alignments, an effort so stunning it creates questions we may never know the answers to.
  • A network of roads, uniformly 30 feet wide, crisscross the four corners (AZ, UT, CO, NM) region, with Chaco as its nexus. These roads carry their own mysteries, as they do not connect the canyon with surrounding communities called outliers, nor do they connect to known resources like forests.
  • The “Chaco Phenomenon” lasted 12 generations, about as long as the United States has existed.
  • Perhaps the Anasazi Chacoans looked at the erratic nature of mother earth and built homes for the gods they called Father Sky. The frustration with tracking the cycles of mother earth would have been dramatic. One year too much rain, then very little for many years in a row. In the desert landscape of Chaco canyon, water is life, and not just to drink, but the game animals they depended on for essential dietary iron, the crops they grew in the fields, a lack of water is life threatening.
  • These great houses, not intended primarily for human occupation, were an invitation to Father Sky to come down and live among them to help them teach mother earth to be predictable and orderly like he is, or perhaps they thought if they built their society is strict alignment with what father sky presented, they could transfer some of his orderly nature and predictability to the world around them.
  • Nothing could have been more important than water, and the water supply could only come with the rains. they must have been obsessed with any idea they thought could influence the rains. Water, water, water. Not only to drink but to irrigate, for the wild plants and animals, even to make the mortar for construction.
  • The Chacoans also possessed advanced astronomy that tracked sun and moon cycles with stunning detail and precision (sun dagger on Fajada butte), and a trade network covering over 2,000+ miles to the south, with scarlet macaws, copper bells, cocoa/chocolate, and seashells found in Chaco.
  • The Chacoans left no record of a written language, did not have use of the wheel, no metal tools, and no domesticated draft animals.
  • There are 21 descendant tribes that claim Anasazi lineage; the 19 Pueblo tribes along the Rio Grande, the Zuni, and Hopi, with limited oral history (at least not available to Anglos) over the 36 generations since Chaco.
  • It is a grand mystery how this place started, why it existed, and why it collapsed.

drawing of the 2012 chaco culture commemorative coin

Chaco Canyon Resources:

National Park Service

The Leading Academic Authority: Dr. Stephen Lekson

DNA Insights

Chocolate? Chocolate!

Mac / PC Computer Simulation of Chaco Canyon

computer program details link