"Cloudy afternoon sky at Aztec Ruins" by U.S. National Park Service , public domain
Aztec RuinsDesigning Aztec Ruins |
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Aztec Ruins
National Park Service
U.S. Department of the Interior
National Monument
Designing Aztec Ruins
Planned Design
The ancestral Pueblos, not the Aztecs, built the elaborate stone structure you’re visiting today and
occupied it for approximately two centuries, between 1100 and 1300 AD. Within miles of Aztec’s West
Ruin are scores of other structures, indicating an extensive, planned community. Clearly, construction of
this magnitude required well organized teams of workers and substantial forethought. Despite such
deliberate design, the use of the building probably changed over time. As you tour the site, consider the
ways in which it was planned, renovated, and repaired much like modern cities.
What is a Great House?
Aztec’s West Ruin is regarded architecturally as a “Great House.” With approximately 400
rooms and 30 kivas, West Ruin is the largest known Great House outside of Chaco
Canyon. Chaco Great Houses are large, typically multi-storied stone buildings on a
formal plan, with core-and-veneer walls, large rooms, plazas, and usually one or more
Great Kivas. Unlike small houses, they show evidence of community-wide activites. The
structure was used as a gathering place, ceremonial center, trade center, work area, and
storage. Most archeologists agree that this building was probably not originally intended
for habitation; most people lived in small, one-story dwellings nearby. However, evidence
suggests that people may have lived in some rooms of the Great House in later years.
Phases of Construction
Construction of Aztec’s West Ruin was episodic and rapid. In fact, the majority
of Aztec West was completed in only 30 years! (For comparison, Pueblo Bonito
in Chaco Canyon took almost 300 years to build.) The first walls built in the West
Ruin were those of Kiva L (stop #15) around 1100 AD. This preliminary
contruction, outlined in dashed blue, is referred to as Stage 1.
Ten years later, approximately 1110 AD, the largest period of construction began at
Aztec West. During this episode, referred to as Stage 2 and outlined in red on the
map, multi-story rooms in the north and east wings were constructed.
Archeologists estimate that about half of the entire Great House was built within
this decade.
· · · · Stage 1 (1100 - 1109)
· · · · Stage 2 (1110 - 1120)
· · · · Stage 3 (1120 - 1130)
The last episode of major new construction began around 1120 AD. During this
episode, referred to as Stage 3 and outlined in green on the map, multi-story
construction of rooms in the west wing took place. These three stages, which
occurred within a span of 30 years, account for the majority of the construction at
Aztec West.
Two phases of renovation to this Great House occurred after the initial, rapid
construction. During the McElmo renovation phase in the late 1100s, outlined in
pink, inhabitants demolished rooms in the eastern north wing and far southwestern
end of the site and inserted numerous large, blocked-in first story kivas.
Additionally, a line of new plaza-facing rooms were added.
During the Mesa Verde renovation phase in the mid 1200s, outlined in blue,
inhabitants subdivided rooms, added sunken kivas to second-story rooms, and
constructed new roofs. It was during this time that a change in the use of the
building may have occurred. The building may have been more heavily used for
habitation, and room use included storage, tombs, and latrines.
· · · · Renovation phase 1 (late 1100s)
· · · · Renovation phase 2 (mid 1200s)
Astronomical Alignments
Many researchers are particularly interested in the way ancestral Pueblos
incorporated the movement of the sun and the moon into their
architecture. No one can prove that the alignments we observe today were
intentional, but the fact that they are found in major sites all over the region
suggests that solar and lunar alignments were a signature feature for
ancestral Pueblo builders.
The long, straight back wall of Aztec West marks both the summer and
winter solstices. From the west corner of the wall, you can watch the
summer solstice sun rise directly up the east corner. From the east corner,
you can watch the winter solstice sun set down the west corner.
(Above) Archeologist
Rich Friedman
documenting the 2006
winter solstice sunset.
(Left) Photograph of
2012 summer solstice
sunrise by archeologist
Gary Brown.
The ancient people may have designed these alignments to keep a precise
agricultural calendar, marking the best times for planting and harvesting
crops. The alignments probably tracked a ceremonial calendar as well.
Modern Pueblos still relate the sun, moon, and stars to their religious lives.
Some still have traditions for choosing and training sunwatchers, people
who are responsible for reading the seasons from the movement of the sun.
Distinctive Characteristics
Core-and-Veneer Masonry
(Above left)
Mesa Verde
masonry
(Above right)
Chaco
masonry
Archeologists often use tree ring dating to figure out when walls were constructed, but
masonry styles also indicate approximate construction period. There are two distinct
masonry styles at Aztec West: Chaco masonry and Mesa Verde masonry. Chaco masonry
developed in Chaco Canyon during the 9th, 10th, and 11th centuries. It is characterized by
organized, meticulous rock layering, chinking, and core-and-veneer masonry, which uses a
central core of mud and stones sandwiched by outer facings of stones in mud mortar.
Mesa Verde masonry, named for its prominence in the Mesa Verde cliff dwellings, is a style
characterized by larger, rounder stones with less emphasis on layering and chinking. The
picture on the left was taken at Stop #14 and shows both masonry styles. The Chaco-style
wall was constructed in the initial stages of construction in the early 1100s while the Mesa
Verde-style wall was constructed during the first reconstruction phase in the late 1100s.
Contrary to previous thinking, archeologists do not necessarily attribute each phase to
population migration. This structure was inhabited continuously, and construction styles
evolved over time. Our current society is no different; we often see houses built in different
time periods neighboring each other on the same street.
Decorative and perhaps symbolic elements like the green layer in the
wall at stop #3 are commonly found here. While the purpose of the
green layer remains unknown, many speculate that masons may be
mimicking the local stratigraphy. Locally, the green siltstone is from an
impermeable formation that the water table sits atop, possibly accenting
the importance of the water table in a symbolic way.
T-shaped doors are common features and usually face the plaza in
ancestral Pueblo Great Houses. Their purpose has also been widely
speculated, ranging from a functional explanation (more elbow room
when carrying pots through doors) to symbolic (directing one’s
attention towards the earth, a sacred place for the ancestral Pueblos.)
Band of green stone
in west wall
Symbolic Layout
The site locations of Great Houses across the Four Corners region, the orientation of the
buildings, and the complex formal geometries of Great Houses suggest that the ancestral
Pueblo builders and architects were incredibly skilled planners and designers. North
Mesa, the first Great House constructed in this area, sits on the mesa above East and West
Ruins. An ancient road runs directly north and bisects the East and West Ruin here at
Aztec (see diagram on right).
The buildings and features at Aztec Ruins were much more than a collection of storage,
living, and ceremonial spaces. Taken together, they were a large-scale representation of
ancestral Pueblo worldview. The symmetrical layout speaks to a grand sense of order and
balance on the landscape. The architecture of Aztec Ruins not only impresses modern
visitors with its massive size and fine workmanship, but inspires them to ponder the goals
and lifeways of its ancient builders.
EXPERIENCE YOUR AMERICA
T-shaped doorway