Thursday, June 1, 2017

Chaco Culture National Historical Park, World Heritage Site, New Mexico

Essence: Chaco Canyon is distinctive for its superbly crafted magnificent structures and sheer number of great kivas and great houses. Pueblo Bonito is the largest prehistoric structure on the Colorado Plateau. Chacoan culture was a triumphant crowning of human achievement and a vibrant society that lasted over 300 years. The subject of in-depth archaeological scrutiny, mysteries remain. This essay describes two short tours: Pueblo Bonito to Chetro Ketl via the Petroglyph Trail; and Casa Rinconada. Two backcountry hikes follow: the Pueblo Alto Loop and the trail to Peñasco Blanco via the Supernova Panel.
Travel: From Durango, travel south on U.S. Route 550 for 82 miles. Just south of mile marker 113 there is a brown sign for Chaco Culture National Historical Park. Turn west on paved San Juan County Road 7900. Turn right onto San Juan CR 7950, 5.1 miles from the highway. Pavement ends at 8.1 miles. The gravel road is wide and swift. However, at 16.8 miles, county maintenance ends and the dirt road is vulnerable to deep ruts. It would be problematic or impassible if wet. Turn back at a wash crossing at 17.5 miles if water is flowing more than a few inches. Upon entering the park at 21.2 miles, the road is paved. 4WD recommended but when the road is dry, 2WD with good clearance should suffice. Allow 2:15 from Durango. There is no fuel available in the park.
Entrance Fees Information
Gallo Campground: This is a National Park Service campground. There are 48 sites and two group sites which may be reserved, a good idea during busy months. Picnic table, fire ring, tent pad, and restrooms with non-potable water. Drinking water is available at the visitor center. Restrooms are closed in winter when porta pottys are available. Plenty of morning sun but no shade throughout the day. Food and ice are not available in the park. Chaco was designated an International Dark Sky Park in 2013. Spend the night in true dark and see the Milky Way and vast regions of space shot with stars.
Time: Plan to spend the entire day in the park.
Difficulty: Visitors are asked to remain on trails; navigation easy; no exposure
Trail Guide: The informative Backcountry Trail Guide with maps is available for purchase at the visitor center.
Latest Date Hiked: June 2, 2017
Quote: Something colossal happened here, an astounding feat of organization for a semi-nomadic people who had never before built anything near this scale...After Chaco fell into decay, there was never a place on the Colorado Plateau with so much concentrated religious wealth.
Craig Childs, House of Rain.

Pueblo Bonito is an immense D-shaped great house located at the center of the Chacoan world. It was constructed in stages over 300 years and is located at the juncture of Chaco Wash and the South Gap.  (THW, photo)

History of the Park 
In a remote canyon in northwestern New Mexico, at the center of the San Juan Basin, lies the remains of a complex agrarian society. Transitioning from a loose aggregation of Basketmaker communities, building began along Chaco Wash on a monumental scale in the mid-800's. By 1175, the great houses of Chaco Canyon were deserted. Architectural marvels and vast treasure lay buried under silt and sand, undisturbed for seven centuries.

In 1849, a column of soldiers in a United States Army expedition from Santa Fe happened upon Pueblo Pintado. Moving westward, each successive cluster of ruins was more remarkable. In 1896, the Hyde Expedition led by Richard Wetherill excavated 190 rooms and kivas at Pueblo Bonito. Railcar loads of artifacts were shipped to the American Museum of Natural History in New York.

In 1906, Congress passed the Antiquities Act to protect prehistoric sites on public lands. A year later, Chaco Canyon was designated Chaco Canyon National Monument. In 1980 it was named Chaco Culture National Historical Park. In 1987, Chaco was designated a World Heritage Site. 

More archaeological research has been conducted at Chaco than any other location in North America. And yet, of the estimated 3,600 archaeological sites within the park boundary, only a small percentage have been excavated. The greater Chacoan community covered roughly 60,000 square miles.

Public architecture at Chaco is unique for its massive scale and perfection wrought by stone masons. There are twelve great houses within the park. Pueblo Bonito is the largest prehistoric structure on the Colorado Plateau. It is a five story, superbly crafted, terraced great house with over 650 rooms and 35 kivas in a half-circle geometric tucked against the south-facing sandstone walls of Chaco Canyon.

Despite all the scrutiny at Chaco, deep mysteries remain. One on-going controversy is population size and class structure. Research by Chacoan authority, Dr. Stephen Lekson, Professor of Anthropology, University of Colorado Boulder, suggests that about 2,000 people lived in Chaco Canyon. The archaeological evidence is unambiguous: the class structure, common for the era, was that of nobles wielding power over commoners.

Fewer than five percent of the population, 50 to 100 nobles, inhabited Pueblo Bonito. Great houses were ceremonial buildings, monuments, temples, and trading centers housing astronomers, priests, master masons, and warriors.  Nobles were clearly influenced by Mesoamerica but DNA studies show they were local people. Commoners lived in nearby unit pueblos with five rooms and one kiva.

Another perplexing enigma is the purpose and extent of road networks that linked the great houses in the canyon to outlying communities. One hundred fifty miles of road have been indisputably documented and another 300 miles of roadway are still visible. Roads radiated from Chaco in all directions. The Great North Road leaves from Pueblo Alto and heads 50 miles toward the San Juan River.  It was engineered to aim straight north without deviation, requiring ramps and stairways carved into bedrock.

Archaeologists question whether the 30-foot wide roads were meant for transportation and trade networks or formal processions. 250,000 timbers were needed to construct over-engineered great house ceilings. Trees were harvested from forests 60 miles away, hoisted and hauled in procession. Studies indicate that most of the timbers came from the Chuska Mountains to the west and from the southern Zuni Mountains. Less than ten percent were hauled from the San Juan Mountains.

Roads supported Chaco's bulk economy. Seashells, chert, and obsidian were imported as well as live macaws from 500 miles away in Guatemala and copper bells from Mexico. Cacao and vast quantities of turquoise were carried from faraway lands. Pottery was fired at the wood source and supplemental corn was grown where water was plentiful. Porters could carry supplies for 250 kilometers before it became counterproductive.

During 300 years of habitation in a desiccated landscape irrigation canals and catchment dams captured sufficient water to grow corn, squash, and beans. At least one 25-year drought occurred. By the late 1100's the Chacoan people had mostly dispersed. While Chaco's influence is clear at Aztec Ruins, Mesa Verde National Park, and the Bluff Great House, those who migrated south created vibrant societies that live on today.

It is believed that the high level of civilization and refinement created at Chaco was the work of indigenous ancestors of present day Puebloans. There is a clear line between earlier societies and modern villages such as Zuni where people reinvented themselves, doing away with the repressive class structure.

Lingering mysteries abound and persist at Chaco, adding to its allure. The creation of wondrous structures speak to traits within us that yearn for excellence in beauty, purpose, and execution.

Pueblo Bonito, Petroglyph Trail, and Chetro Ketl
Chaco Loop Road is one-lane, one-way. Pueblo Bonito and Chetro Ketl share a parking lot. The trail through Bonito is 0.6 mile long. Pick up an interpretive guide at the visitor center.

Pueblo Bonito means "pretty village" in Spanish. The great house was constructed in stages from 850 to 1150. It was the epicenter of the Chacoan world; one archaeologist dubbed the great house and immediate surroundings "downtown Chaco."

Masonry techniques were unique for the time and evolved over the centuries. While different masonry styles are represented at Bonito, they are typically core and veneer as seen below at the southeast corner.

Four types of doorways were used in great house construction. Most common are small doors with a high sill. Shown below is a series of four doors at rest under a cloudy sky.

Vigas cast long shadows in full sun.

There are seven corner doors in Bonito which serve as astronomical markers. In one interior room Wetherill found a stockpile of 198 cylinder jars with black-on-white Mayan designs. The unique pottery forms were filled with turquoise and cacao, Chacoan currency. Nobles controlled the production of turquoise beads made in commoner houses. Stacked burials of nobles were covered in turquoise, shell, and macaw feathers. (THW, photo)

There are three great kivas in the plaza and many smaller ones crowded together.

Chaco Canyon lies in northwestern New Mexico along the upper reaches of Chaco Wash, a 100 mile-long tributary of the San Juan River. An ephemeral stream, the wash cut Chaco Canyon through Cliff House Sandstone, the upper member of the Mesa Verde Group. It is underlain by the Menefee Formation, a dark shale containing thin sandstone strata and coal. Find the intersect between structures and the cliff rock from which they were created.

The Navajo named the pueblo, "house where the rocks are propped up." Threatening Rock was a colossal standing rock detached from the cliff. Chacoans buttressed it with a supporting masonry terrace. The column collapsed in 1941 demolishing a portion of the great house.

A trail guide for the 0.25 mile Petroglyph Trail is available at the visitor center. Incised lines are possibly sharpening grooves for axes, awls, and knives. Stone tools were used to create petroglyphs and to construct buildings.

This complex panel has anthropomorphs, a venomous snake, and spirals spinning off each other.

Chetro Ketl is the second largest Chacoan great house. The earthen plaza rests on an artificially raised platform twelve feet above the valley floor. There are a cluster of subterranean kivas, including a great kiva. These massive, perfectly circular structures had standardized architectural features. Looking at the image below, the circular masonry-lined pits seated four wooden pillars that supported the domed roof. The timbers stood on stacks of sandstone disks, shown. Notice the raised floor vaults and firebox. A staircase served as entryway from the plaza level. A low masonry bench encircles the room. The square wall niches held offerings. Finally, kivas possessed a sipapu, a small hole that served as passage to and from the underworld.

Chetro Ketl is distinctive for its elevated kiva and 500-foot-long undeviating back wall. It is aligned precisely with east-west cardinal points. (THW, photo)

Casa Rinconada 
The trail through Casa Rinconada and nearby sites is 1.2 miles long but the great kiva is just a few steps from the parking area. Casa Rinconada is the largest excavated great kiva in Chaco Canyon. It was constructed on a hill within a community of small villages. The kiva accommodated hundreds of people for ceremonial purposes.

The kiva's diameter is 64 feet. Thirty-four niches are tucked into the inner wall above the masonry bench. Casa Rinconada is aligned with solar, lunar, and cardinal points. The northern entryway is aligned precisely with true north. Dr. Lekson claims that cardinal directions are obsessively embedded in Chacoan architecture. As interest in archaeoastronomy gains traction, people come to Casa Rinconada at the Summer Solstice to watch first light enter a window and cast a rectangle of light inside a niche. While archaeoastronomers are not sure whether this particular alignment is a true solstice marker, other astronomical alignments in Chaco have been verified. (THW, photo)

Wall detail on the north antechamber exterior.

Backcountry Trails
Two of the four backcountry hikes at Chaco are shown on the map below. The Pueblo Alto Loop Trail is the black-line route. Peñasco Blanco is depicted in blue. Backcountry hikers must carry a permit, available at the visitor center or trailhead. There is little or no shade; carry plenty of water.

Pueblo Alto Loop Trail
This trail begins from the Pueblo del Arroyo parking lot at elevation 6,120 feet. It is a six mile stem-and-loop with 400 feet of elevation gain. The hike will consume between two-and-a-half and four hours. Highlights include two Chacoan passageways, Pueblo Bonito Overlook, Pueblo Alto Complex, and the Jackson Stairway.

From the parking lot head northwest toward Kin Kletso on a dirt road that parallels Chaco Wash and the canyon cliffs. The valley floor is thick with big sagebrush, four-wing saltbush, greasewood, and blackbrush. Cottonwoods edge the arroyo.

At 0.3 mile, the Alto Trail splits off to the right passing by Kin Kletso, "yellow house" in Navajo. According to the information placard at the site the great house was built over a ten year period in the early 12th century just before construction at Chaco ended. The masonry style is McElmo characterized by the use of larger, softer, and lighter sandstone slabs.

The well-armored escarpment is broken by a two to three foot-wide crack, an ancient passageway. It is a delightful, easy Class 2 scramble to the cliff top.

Emerge from the crack onto a sandstone bench that overlooks Kin Kletso.

Follow cairns across sandstone sheets bearing southeast. Pass pecked basins typically carved near cliff edges on sandstone benches. Turquoise was found in some basins.

In February, 2017, an elk herd stoically watched as we passed.

Fossilized shrimp burrows, masonry terraces, and stone circles are explained in the trail guide.

Leave the Pueblo Alto Trail and take the short spur to the Pueblo Bonito Overlook at one mile. (THW, photo)

From the overlook see the graceful sweeping curve of Pueblo Bonito. The plaza is bifurcated into eastern and western halves by a room block aligned with true north. Several roads entered the canyon through the South Gap. Archaeologists think that regions south of Chaco were even more influential than those to the north. The northern boundary is limited and defined by the San Juan Mountains. Chacoan influence extended west to Hopi, east to the Rio Grand River, and south to the Mogollon Rim. (THW, photo)

Return to the Alto Trail and begin the gentle climb to the Pueblo Alto Complex. A Chacoan Road linking Pueblo Alto to Bonito and other buildings on the canyon floor was cleared in the 1970's but it is hard for the untrained eye to detect. Look for stacked rocks curbing the boarders. Masonry steps were constructed between tiers of sandstone. Below, New Alto is seen from a distance.

At 1.8 miles, take the left branch to visit New Alto. It is a two story great house with rooms arranged symmetrically around a central kiva. The site has been stabilized but not excavated. Walk around the structure and then take a cut-across trail to Pueblo Alto just 0.2 mile afar.

Pueblo Alto, elevation 6,440 feet, is the literal highpoint of the hike. It is the largest structure in the complex and the only one that has been excavated. However, it remains mostly buried. As with Bonito, fewer than five percent of the rooms show evidence of habitation.

Pueblo Alto was the first great house built on the Great North Road. At an opening in the north wall, several roads radiate to northern outliers including Salmon Ruins on the San Juan River and Aztec Ruins on the Animas River. It is curious that Chaco wasn't built in Aztec, New Mexico to begin with. The great house at Aztec was the single biggest construction project done in a decade at the height of Chacoan power, post 1125. Aztec maintained the same class structure of nobles and commoners and fell into rapid decline shortly after completion. Earl Morris fully reconstructed the great kiva at Aztec between 1916 and 1922.

The hilltop site has a full-circle view of the endless horizon. The Jemez Mountains are east; Mt. Taylor is south; the Chuska Mountains are west; Huerfano Mesa, the San Juan Mountains and La Plata Mountains may be seen in the north. The Puebloans communicated great distances using signal fires. A fire box was found at Pueblo Alto. A repeater signal sent the message from Huerfano Mesa to Chimney Rock and from there to Mesa Verde. Blocky McElmo style is shown in this masonry detail.

The Mesa Verde Group is overlain by Lewis Shale which forms the plain north of Pueblo Alto. Walking is flat and easy heading east on a well-defined dirt path hemmed in by ephedra, prickly pear, and native grasses. Be watching for the Jackson Stairway on the opposite wall of a box canyon. Reach the stairs at three miles.  The stairway was carved into the cliff face to enhance travel between Chetro Ketl and Alto Mesa. Photographer William Henry Jackson traveled with the Hayden Survey of the western United States in 1877.

Walk to the south end of the mesa rim and squeeze 25 feet down a boot-wide crack or stem the breach.

From the Chetro Ketl overlook, gaze into the great kiva. An arc of rooms encloses the elevated courtyard and tower kiva.

Signs point to road segments and the remains of a broad ramp that ascended from the floor of the canyon to the cliff top. Close the loop at the spur to Pueblo Bonito Overlook. A second visit will reveal the great house in different light.

Descend the Chacoan passageway. At the bottom find a boulder covered in fossilized, glossy sea shells. It attests to the marine origin of Cliff House Sandstone during the Cretaceous Period.

Peñasco Blanco Trail
This trail begins from the Pueblo del Arroyo parking lot. It is a 7.8 mile out-and-back with 300 feet of elevation gain. Total hiking time is three to five hours. Highlights include a high concentration of rock art, the Supernova Panel, and the western gate of Chaco Canyon, Peñasco Blanco.

The track is shared with the Pueblo Alto Trail to Kin Kletso and then carries on to Casa Chiquita at one mile. The compact great house was built on a rise. A square room block surrounds an elevated kiva.

The trail continues down Chaco Wash as an historic Navajo wagon road once did, shuttling goods between Wetherill's Pueblo Bonito Trading Post and points west.

Keep a keen eye out for petroglyphs on random boulders at the base of the Cliff House Sandstone. Chaco Canyon has the most Basketmaker sites found anywhere, dating from the 6th century. The sites are contiguous in the canyon and so is their rock art.

The 0.3 mile Petroglyph Trail begins at 1.5 miles. It runs along the cliff adjacent to the main trail. Here you will find the largest concentration of petroglyphs and inscriptions in Chaco Canyon: Puebloan, Navajo, and cowboy engravings. The initial 15 foot panel features geometrics which some attribute to the shaman's inner eye. The panel shown below is 35 feet above the canyon floor. The three elements are a bighorn sheep, an anthropomorph, and a katsina (supernatural being) mask. Off image-right are faint but exceedingly beautiful designs beside sandal tracks going up the wall.

Rejoin the main trail and walk on the floodplain. After crossing Chaco Wash at elevation 6,060 feet, the trail abuts the cliff directly below Peñasco Blanco. The Supernova Panel is located here, three miles from the trailhead on the ceiling of a small overhang. The red pictograph depicts a star, crescent moon, and human hand.

On July 5, 1054, Chinese astronomers recorded the rare explosion of a supernova in the constellation of Taurus. The Crab Nebula is the supernova remnant. It was as bright as the full moon, visible mid-day for a month. This occurred when the great houses of Chaco were at the height of power. On that morning the horns of the waning crescent moon pointed west. The middle finger of the hand points to where the supernova rose.

On the vertical wall in the image below is a pecked and painted solid sphere with two concentric circles. Red paint flows out to the right. Halley's Comet passed Chaco twelve years after the supernova in 1066. Notice the swallow nests attached to the wall.

Peñasco Blanco, "white bluff," is 0.8 mile further. The trail steps up the cream-colored sandstone and tops out on a mesa at elevation 6,270 feet. The great house overlooks the confluence of Chaco Wash and Escavada Wash. The site is located at the terminus of several roads at the western entrance to Chaco Canyon. We searched fruitlessly for the 30-foot-wide Chacoan road going west. Blanco is in line of sight with Bonito and Una Vida, eight miles away. Pueblo Alto, signal fire location, is also visible. (THW, photo)

Wetherill and Navajo workers searched some of the rooms looking for turquoise, but Peñasco Blanco remains chiefly unexcavated. The great house with its unique oval layout was constructed over a 300 year period and different masonry types are evident. Walking around the lofty pueblo I felt a sense of timelessness and shared human experience.

Pueblo Del Arroyo Upon returning to the trailhead visit the "village by the wash." It is notable for three concentric, circular walls. In contrast, this razor-sharp corner is typical at Chaco. Circular or linear, exceptional craftsmanship is the esthetic norm in Chaco Canyon.

The condition of the road and remoteness of Chaco Culture National Historical Park is its saving grace.

1 comment:

  1. A very comprehensive guide to a priceless treasure. I think its remoteness has been key to its preservation.