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Mesa Verde Cliff Dwellings (Colorado USA)

Credits: ©2008 wikipedia.com

Mesa Verde is best known for a large number of well preserved cliff dwellings, houses built in shallow caves and under rock overhangs along the canyon walls in Southwestern Colorado. Around 14 centuries ago, the nomadic Anasazi -- or Ancestral Puebloan -- people chose to settle down and build permanent homes near their planted crops. As the tribe prospered, members migrated outward to build "cliff dwellings" in a variety of locations-Mesa Verde chief among them. From this network of cities, Anasazi culture flourished for hundreds of years. Then, according to the US National Park Service, they migrated south to New Mexico and Arizona, and by 1300, the Ancestral Puebloan occupation of Mesa Verde ended.

 

Mesa Verde Cliff Dwellings 2

The structures contained within these alcoves were mostly blocks of hard sandstone, held together and plastered with adobe mortar. Specific constructions had many similarities, but were generally unique in form due to the individual topography of different alcoves along the canyon walls. In marked contrast to earlier constructions and villages on top of the mesas, the cliff dwellings of Mesa Verde reflected a region-wide trend towards the aggregation of growing regional populations into close, highly defensible quarters during the 1200s.

While much of the construction in these sites conforms to common Pueblo architectural forms, including Kivas, towers, and pit-houses, the space constrictions of these alcoves necessitated what seems to have been a far denser concentration of their populations. Mug House, a typical cliff dwelling of the period, was home to around 100 people who shared 94 small rooms and eight kivas built right up against each other and sharing many of their walls; builders in these areas maximized space in any way they could and no areas were considered off-limits to construction.

Not all of the people in the region lived in cliff dwellings; many colonized the canyon rims and slopes in multi-family structures that grew to unprecedented size as populations swelled. Decorative motifs for these sandstone/mortar constructions, both cliff dwellings and non-, included T-shaped windows and doors. This has been taken by some archaeologists, such as Stephen Lekson (1999), as evidence of the continuing reach of the Chaco Canyon elite system, which had seemingly collapsed around a century before. Other researchers see these motifs as part of a more generalized Puebloan style and/or spiritual significance, rather than evidence of a continuing specific elite socioeconomic system.

CLIMATE

Mesa Verde enjoys a fairly moderate climate for its elevation but is generally colder than most areas of the deserts. Winters are mostly sunny but cold. Average midwinter (January) highs are about 40 degrees F. with lows of about 15 degrees F. Cold-snaps do occasionally occur but are short-lived. Winter snowfall averages about 90 inches a year causing closure of most of the park. The park re-opens in the spring as the weather warms and occasional rains bring wildflowers to high country meadows and mesa tops. During the summer, temperatures seldom reach more than 85 degrees F. July's mean daily maximum is 82 degrees F.; its mean daily minimum is 45 degrees F..

SETTING

Mesa Verde National Park is located in the high plateau country of southwestern Colorado. The park lies atop a high mesa that rises from the canyon of the Mancos River, a tributary of the San Juan River. The Mancos has cut a deep, broad valley along the eastern and southern edge of Mesa Verde, which in turn is dissected by 15 canyons formed by smaller streams. This erosional action has thus created many smaller mesas. Two of these, Wetherill and Chapin mesas, provide the primary access to most of the park's public archeological sites. Mesa Verde National Park encompasses 52,122 acres, about 81 square miles. It runs about 9 miles both east-to-west and north-to-south. Elevation on Mesa Verde varies between 6,000 and 8,500 feet.

Following is an additional Article
by Joe Zentner

The Anasazi (a Navajo word meaning 'ancestors of our enemies', also preferably known as Ancestral Puebloans) cultural traditions began to emerge early in the first millennium, presumably from nomadic bands who hunted the game and gathered the wild plants of the Four Corners area. The early Anasazi lived as pithouse village farmers along stream bottoms and mesa tops.

They occupied lodges built of mud-plastered timber and brush constructed over shallow excavations in the ground. They raised corn, beans and squash--crops that originated well down in Mexico. They supplemented their farm produce with game (especially rabbits) and wild plants. They made pottery, following a technology that originated in Mexico. About 500 A. D., they replaced traditional spears and throwing sticks (sometimes called "atlatls") with the bow and arrow, a much more efficient weapon that evidently originated somewhere to the north.

They distinguished themselves by producing elaborate and finely woven basketry. The later Anasazi, in the second half of the first millennium, began building their lodges and other structures, not over pits, but as contiguous rooms on the surface of the ground. In some instances, they built jacal-style walls, that is, walls of adjoining upright poles plastered with mud or adobe. They sometimes built pithouses that may have served, not as housing, but as chambers for clan social gatherings, crafts and ritual prototypes for the ceremonial chambers called kivas.

Late in the first millennium, the Anasazi began to build small cities - pueblos of finely crafted walls of masonry. They would leave well-planned communities, innovative architecture, superb masonry and large circular semisubterranean - great kivas - as their collective signature. At the peak, as many as 100,000 Anasazi may have occupied the Four Corners region.

The Mesa Verdan Anasazi
Anasazi pithouse village farmers moved into Mesa Verde about the middle of the first millennium, settling primarily on the mesa tops. Typically, they built their lodges over roughly square- or rectangular-shaped pits. They used crude wooden tools to excavate the pits and woven baskets to haul away excess soil. They set four main ponderosa pine timbers, one at each corner, to anchor the walls and support the roof.

They divided the interior into a living room with a fire pit and an air deflector and an antechamber with storage bins. They farmed the mesa tops, hunted rabbits and deer, gathered wild plants, crafted pottery, used the bow and arrow and wove fine baskets.

About the middle of the 8th century, the Mesa Verdans, their population prospering and growing, began to give up their pithouses in favor of surface structures, building long rows of contiguous rooms with the jacal-style walls. Within another one to two centuries, they had become masters of masonry, building two- to three-story pueblos with 50 or more rooms.

They cleared more of the mesa tops to open up new fields for their crops. They began to produce a more elaborately designed pottery. A century into the second millennium, the Mesa Verdans, now with a population of perhaps 5000, did a strange thing. For some mysterious reason, they began to abandon their pueblos on the mesa tops and construct new pueblos in the great canyon alcoves.

Calling on all their skills for community planning, architecture and masonry, they built compact and defensible stone cities with many small rooms that were used for living, cooking, working and storage. In the midst of their new villages, they built, for the first time, multistory stone towers.

In the natural courtyards of their communities, they built large underground kivas. They continued farming, hunting and gathering. They raised their craftsmanship to the level of art. The reason for the move from the mesa tops into the canyons? Possibly for defense. But against whom? No one knows. It is one of the great mysteries of Mesa Verde.

Two to three centuries into the second millennium, the Mesa Verdans did another strange thing. Like Anasazi across the region, they began to abandon their ancestral homeland. Family units, clans or possibly entire villages migrated to the southeast or south, where they built new pueblos or joined other Puebloan peoples, sometimes in very large and populous communities. What were the reasons for the migration?

Possibly the threat of raiders, the onset of prolonged drought, the depletion of timber and other resources, the exhaustion of arable soil, the collapse of their religious and political infrastructure, the lure of other pueblos, different religious concepts, the promise of greater resources and a better life, or some combination of reasons, but no one knows for sure. The abandonment is perhaps the greatest mystery of Mesa Verde.

Following is an additional Article
by Kelly Hart

I visited Mesa Verde in Colorado near the Four Corners. This was my first encounter with the "ruins" of the Ancestral Puebloan people, progenitors of the Pueblo and Hopi nations. I had heard about Mesa Verde since I was a kid, but nothing could prepare me for the awesome reality. Despite the influx of tourists, there is a peaceful and spiritual quality that persists. The most famous aspect of what was left behind there are the cliff dwellings, which are certainly magnificent.

These finely crafted rock structures emerge from huge alcoves within the cliff faces, and from a distance resemble swallows' nests, fitting into the surrounding rock just as naturally. Actually the cliff houses represent the culmination of about seven centuries of habitation at Mesa Verde.

Then around 1300 AD the people abruptly abandoned their homes and moved south and southeast to establish other communities. There is much speculation about why they moved, but the most likely cause was a prolonged period of at least 12 years of drought.

The cliffs were only occupied for the last two centuries at Mesa Verde; before that, all habitation was on the mesa above. At first the people made rectangular pit houses that were dug partially into the ground and then built up with poles and sticks plastered with mud.

The entrance was via a hole in the roof with a ladder descending to the floor below. Archeologists believe that from this simple pit house both the freestanding masonry pueblo and the underground circular kiva evolved. The cliff dwellings combined both interconnected pueblo "apartments" and kivas, which were used for ceremonial and community functions. Some of the larger cliff dwellings may have housed over a hundred people.

Most of the Mesa Verdeans lived in this communal way, but there were also many smaller housing units scattered throughout the area. It is obvious that they were a very cooperative society. Little did they know that their style of architecture would become so enormously popular many centuries later. Pueblo or Santa Fe style building can be linked directly to them.

The Spanish introduced modular adobe blocks that make the construction go faster, but the simple stacked rectangular shapes with protruding vigas is native American. These people were primarily farmers, growing squash, corn and beans in terraced garden plots on the mesa tops. They carefully guided water to their gardens. The mesa itself slopes gently toward the south, which improves the solar gain for gardening, and the colder air slides down the canyons and off the mesa, which increases the growing season.

There is a lot of speculation about why they decided to start building communities within the cliff faces. Some think it was for defensive purposes, although there is little evidence of violence to support this. My sense is that they moved to the cliffs for comfort. Some enterprising individual or family probably tried building a stone house on one of the many cliff ledges that faces south and soon realized that there were many advantages, which were pointed out to the others. Sealing off a cave or cliff alcove with rock walls effectively makes the room a part of the cliff itself. It's like digging into the ground to take advantage of the cool in the summer and the warmth in the winter, but under the rock ledge they were also protected from the rain and snow and had much more thermal mass to buffer temperature extremes. Facing south, or southwest, as many of the cliff dwellings do, would allow the sun to enter the openings into the interior and also warm the stones, which would give off heat at night. During the summer, when the sun is high in the sky, much less sun would reach the buildings and they would remain cooler.

I got an indication of how well solid rock can modulate temperatures at another stop. On the outskirts of Moab, Utah is a 5,000 square foot dwelling blasted out of solid monolithic rock, called Hole-in-the-Rock. It is open for tours, so I checked it out and was informed that the temperature stays about 65 degrees F. all year round. Moab is at about 4,000 feet elevation, so it is a warmer climate than Mesa Verde, but even so the cliff dwellings must have been fairly comfortable most of the time.

I couldn't help but compare what the ancestral Puebloans have achieved with what I have been advocating about sustainable architecture. They score remarkably high! The rooms are very compact, often sharing walls with each other (which makes for less transportation of building materials and the adjacent rooms help keep each other warm.)

The rooms are often stacked on top of each other (I saw as many as four stories), which again conserves space, materials, and heating energy. There is very little wasted space; even the tops of the pueblos and kivas were used for community activity. Most of the cliff dwellings were oriented to collect solar energy. Even though they didn't have glass to keep the rooms cozy, they compensated by using quite small entrances and ventilation holes, which could be sealed with slabs of rock or hides when they wanted. Being built into the cliff face, they did not overheat in the summer.

Because of these factors they were relatively energy efficient, requiring less wood for heating. The materials they used to build with were definitely local and natural, being just the sandstone and adobe found in the area. Very little wood was used, just small vigas to support the floors of the various stories or the kiva roofs. What wood they did use was obviously not milled. Deforestation was likely an issue for these people, as it is for us.

I'm sure they recycled building materials as there is much evidence of remodeling over time. They most certainly built to last, as much of their work has survived some seven centuries without any maintenance. The Park Service has stabilized some of the structures, but they say only about 10% of what is there now has been done since the natives left. In fact you can usually tell which work was done in modern times because it is much cruder than the original work, which was carefully carved with stone tools and then plastered to make very smooth, colorful walls.

Most of the original colored plasters have not lasted. They did not have enclosed greenhouses, for obvious reasons, but they did grow all of their food nearby, basically on the mesa top that was their roof. They also had domesticated turkeys (the feathers were used for making blankets) and dogs (which provided hair that was woven into belts, etc.)

With all of this sustainability, why were they unable to sustain their culture at Mesa Verde? As I mentioned earlier, the likely cause was a prolonged drought that made it very difficult to provide food for the thousands of people living there.

This could be the final message from these ancestors: ultimately we live at the mercy of mother nature. They were able to move on to other places where streams provided water for their gardens. Where could we move if our climate becomes inhospitable or we have polluted the waters or poisoned the air or our great machines cease to run?

Relevant books:

The Mesa Verde World

Mesa Verde National Park

Mesa Verde: The Story behind the Scenery


Resources

Earth Architecture

Earth Building