The Forgotten Tombs of Guirún and the search for the
largest megalith in North America
The valley of Tlacolula in Central
Oaxaca, Mexico, is home to one of the largest concentrations of megalithic
monuments in Mesoamerica. The origin of these structures is conventionally
attributed to the Zapotec and Mixtec peoples, who occupied the area since at
least 500 B.C. Their largest and most important sites were Monte Alban and
Mitla, characterized by a sophisticated stone architecture, magnificent
underground tombs and advanced metalworking techniques.
The palaces and underground tombs of Mitla, with their
intricate stone decoration, would cause the greatest impression in the early
Spanish Conquistador and in later travelers during much of the 17th
and 18th Century. Early chroniclers marveled at the extraordinary
workmanship of these structures and the immense size of the stones – buildings
which were “prouder and more magnificent
than any that they had hitherto seen in New Spain. [1]”
These early chroniclers described vast halls supported by
round pillars consisting of one stone, and immense doorways built with huge
monolithic lintels and jambs. An even greater marvel were the stone mosaics
that ornated the walls, consisting of an infinite number of small rectangular
stones “as smooth and regular as if they
had all come from one mould”. And, more wonderful still, these stones were
“adjusted without a single handful of
mortar”, a feat “inexplicable even to
the greatest architects”. All of this was accomplished, according to
another source, wholly “without tools,
with nothing but hard stones and sand. [2]”
The palaces of Mitla and their impressive stone architecture
have been covered at length in a previous article on this blog, which can be
accessed here.
A few years ago I came across a brief description and some
black and white pictures of what appeared to be an enormous cruciform
megalithic structure in the mountains near Mitla. The report in question had
been published in 1909 by the American archaeologist Marshall H. Saville and
only named the site as Guiaroo [3].
Initial enquiries into the location of the mysterious ruin
in 2017 turned out to be largely unsuccessful. We were, however, able to locate
another interesting megalithic tomb on the grounds of the abandoned Hacienda of
Xaaga (See here for a description of our find).
Finally, in March of 2020 our friend Ludovic Celle from
Oaxaca City, who had himself visited the site a couple of years earlier and
provided GPS coordinates, put us in touch with a local guide, Misael Martinez,
who also knew the location of the ruins. His experience proved invaluable not
only in locating the cruciform structure, but also a second tomb and various
other ruined structures not mentioned by Saville in his initial report of the
site.
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| The "Palace" of Guirún, in the Upper Group. The Temple of the Two Rooms appears as a large stepped pyramid on the opposite side of the rectangular Plaza. The cruciform chamber is located on a ridge less than 200 meters from the Palace. [Photo by Author] |
The ruins of Guirún (or Guiaroo) are located on a hilltop
some 5 kilometers to the NE of the little town of Xaagá, amidst spectacular
cliffs and deep canyons. The site was studied by Gary M. Feinman and Linda M.
Nicholas in 2004, which conducted a comprehensive survey of the remaining
structures but did not conduct any excavations [4].
The largest building is called the “Palace of the Two Rooms”. It is in fact a group of four ceremonial
structures facing a square plaza with a large terraced pyramid on the eastern
side. The temple on the top of the pyramid is still in a reasonable state of
preservation and consists of two large rooms approached by a stairway, from
which the entire complex receives its name. The plan of the structure is
similar to that of the largest palaces at Mitla, but lacks the same
high-quality workmanship and stone decoration. It is quite possible that
underground tombs may exist under each of the ceremonial platforms to the North
and to the East. There are also traces of fortifications and of what could be a
small Mesoamerican ball game to the South of the palace.
The cruciform structure, often called a “tomb”, is found
less than 200 meters from the main Palace, on another low ridge covered in
bushes and shrubs, next to a ruined pyramidal mound some 10 meters high.
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| A view of the Cruciform chamber looking North. [Photo by Author] |
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| Another view of the Cruciform chamber looking East. Note the immese size of the stone blocks forming the walls and the perfect jointing along the exposed face. [Photo by Author] |
There are few words to describe a structure so entirely
unique in the panorama of Mesoamerican architecture. Its measurements are given
by Saville as 32.8 ft. (10 meters) along the East-West axis and 28.6 ft. (8.7
meters) along the North-South axis. It is in the shape of a cross, precisely
oriented to the cardinal directions, and has the entrance to the West. The
walls, up to 2.5 meters (7.5 ft) high, consist of enormous megalithic stone
blocks laid without mortar or cement. The largest stone block, located on the
southern wall of the western arm, measures 12.5 by 3.3 by 3 ft, or
approximately 3.8 by 1.0 by 0.9 meters, weighting an estimated 10 tons or more
in its finished state. A total of 52 stone blocks were employed for the
construction of the chamber, which remained unroofed. The interior walls, with
the sole exception of the terminal wall of the southern arm, are entirely
decorated with intricate geometric pattern resembling the mosaic stonework at
Mitla – except that the carvings were applied here directly on the stone
surface. The patterns run on three bands, the ones at the bottom and the top
resembling waves or swastikas, with a labyrinthine design in the middle band.
Traces of red and white paint still survive in places.
The large stones were pinched into place by means of holes
in the back of them, where levers were most certainly inserted. One huge stone
block lying near the chamber also shows two enigmatic U-shaped bosses in relief
that served possibly for transportation.
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| The author posing next to the largest stone block on the souther wall of the western arm. [Photo by Author] |
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| A close-up view of the largest stone block on the southern wall of the western arm. Note the curious embossment in the middle, which probably served to ensure a tight fit the other stones. Similar features have been documented at other megalithic sites, such as at Ollantaytambo in Peru. [Photo by Author] |
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| Another view of the western and southern arm of the cruciform structure, each consisting of a single stone. Notice the holes in the back of the stones, possibly for the insertion of levers. [Photo by Author] |
It has been suggested that the “tomb” was left unfinished,
due to the presence of several large construction blocks abandoned in the
vicinity and the absence of a roof. This seems to contrast, however, with the
evidence from the exquisitely carved decoration and traces of paint on the
inside. Saville remarked that the debris filling the chamber at the time of
discovery did not contain the slightest trace of human remains or other pottery
fragments by which the structure could be dated. There is also no trace of a
floor, so it is not clear whether the structure actually rests on bedrock or
continues underground. Compass readings show that the longest arm is oriented
about 17 degrees to the East of North. As such, Guirún would join a long list
of Mesoamerican sites with anomalous orientations, including Teotihuacan,
Chichen Itzá and Tula, which are all oriented between 15.5 and 17 degrees to
the East of North.
Our friend Ludovic Celle from Oaxaca also noticed a close
similarity between the geometric patterns that ornate the walls of the
cruciform structure of Guirún and those of the Palace of the Columns at Mitla.
These differ significantly from the mostly plain decoration of other
underground tombs, which only contain isolated mosaic panels. Ludovic also
created a great 3D reconstruction of the tomb which may be accessed from the
following link: https://www.artstation.com/artwork/kAG8y
It is possible that the cruciform structure of Guirún was therefore never intended as a tomb, but as a ritual chamber or astronomical observatory.
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| A view of the interior of the cruciform chamber, looking East, from which it is possible to appreciate the remarkable decoration on the inside. [Photo by Author] |
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| Another view from the interior of the cruciform chamber, looking North. It is possible to appreciate the three different patterns that form the lower, middle and upper band. [Photo by Author] |
At a distance of about one mile from the Upper Group and the
cruciform structure, we found the remnants of another ruined palace supported
by massive stone embankments. Inside the courtyard of this second palace we
found the entrance to another tomb, which was also briefly described by
Saville. This is a cruciform structure, measuring some 24 by 22 ft, or about
7.3 by 6.8 meters along its two horizontal arms, built entirely underground of
loose cemented stones covered with a roof of large megalithic flagstones. The
workmanship of this structure, which was most certainly a tomb, appears rather
crude if compared to the other examples of cruciform tombs from Mitla and
Xaaga, and does not share the least similarity with the exquisite finishing of
the cruciform structure in the Upper Group, neither in the use of large
megalithic stones nor in the quality of the decoration. The walls were covered
in plaster and painted bright red and white. Only traces of the original
plastering and paint remain. Of a third megalithic tomb described by Dupaix in
1805 as containing a monolithic stone pillar in the middle and carved mosaic
panels, we could find no trace.
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| The very narrow entrance to the other small cruciform chamber in the Lower Group of ruins at Guirún [Photo by Author] |
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| A view of the interior of the small cruciform chamber in the Lower Group. The roof is formed of enormous megalithic stone slabs, but the general construction appears quite crude. The walls still retain traces of red and white paint. [Photo by Author] |
Our attention was then drawn to some of the nearby quarries.
A large prehispanic quarry was first reported by archaeologist Nelly Robles in
1994 at a site known as La Cuadrada,
about one hour from Guirún, containing some 57 worked pieces. Unfortunately,
the limited time available did not allow for a thorough examination of this
site. Most of the stones seem to be of comparable size to some of the largest
stone blocks at Guirún. We explored instead another stone quarry located near
the village of Xaagá, near a rock face known simply as La Peña, where prehistoric rock art is also visible. We found there
one very large stone, possibly a lintel, measuring approximately 4 by 1.5 by
1.25 meters. The approximate weight of the stone would be in the range of 15 to
20 tons. Our guide drew our attention to the fact that most quarries are
located in close proximity to small streams, implying that water was perhaps
employed to facilitate the cutting.
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| A view of the megalithic stone quarry at the site of La Peña, near the village of Xaaga. [Photo by Author] |
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| The largest stone block still lying in the quarry at the site of La Peña, measuring some 4 meters long - most likely an unfinished lintel or pillar. [Photo by Author] |
We also learnt of one immense stone block lying on a
mountain slope near the village of Unión Zapata, some 2 kilometers to the East
of Mitla. The site is known as Guigosj, meaning “fallen stones”. Archaeologist
Nelly Robles describes at least 6 huge stones “of uncommon size” lying horizontally in the quarry. In her 1994
report, Dr. Robles observed that “at
first, the enormous size and monumentality of the stones made us doubt that
these could have been quarried intentionally; yet the perfection of the cuts
and their geometric shape indicated otherwise [5].” The largest stone would
have had the enormous dimensions of 12 meters long by 4 meters wide and 2.5
meters high. Assuming a specific weight of the stone between 2.3-2.5 tons per
cubic meter, its weight could be close to 300 tons.
Also in this case, however, time limitations did not allow
us to fully explore the site, which we will leave for a future expedition.
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| Various large stones found abandoned in the vicinity of the cruciform structure in the Upper Group of ruins of Guirún. Note the holes in the back of the large lintel and the curious U-shaped bosses on the other stone block in the foreground - probably another transporation device. [Photo by Author] |
Judging from the enormous number of stones still abandoned
in the quarries, and their immense size, it is clear that a colossal building
program in the valley of Tlacolula and Mitla was suddenly interrupted and
remained unfinished. In her 1994 study, Dr. Nelly Robles documented at least
nine major quarries in the area of Mitla alone, containing an estimated 200
megalithic stone blocks in various stages of completion, the majority of which
in the 5-10 tons range. This would be enough to build at least four cruciform
structures like the one at Guirún.
It is not clear what circumstances led to the abandonment of
such a colossal building program. When the first Spanish Conquistadors visited
Mitla in the 1520’s, they found the city already in ruins, after the Aztecs had
conquered and sacked it in 1494. Perhaps it was the Aztec conquest that caused
the abandonment of the quarries, or maybe this occurred much earlier. A recent
2019 study found evidence of a massive landslide to the north of Mitla that may
have contributed to the abandonment of the site and the collapse of Zapotec
civilization. The same study also found evidence of what could be buried
pyramids or structures under the landslide, suggesting that the avalanche could
have occurred within historical times [6].
Another mystery is the technique employed for cutting and
transporting the enormous stone blocks. The stone itself is a type of andesitic
toba, which would have required stone or metal tools for its extraction and
polishing. A further question is posed by the intricate grecques and
ornamentation found on some of the blocks – the finest being those that
decorate the walls of the cruciform structure of Guirún. The perfect right
angles and minute details suggest almost the use of molds, as the design is
always repetitive and perfect, without the slightest error or deviation. One
may also consider the possibility that the stone is in fact a type of
geopolymer and that it was cast into place rather than quarried and
transported. This possibility may only be confirmed by future studies and
analyses.
While this is only a suggestion for now, there is something
in the obsessive repetition of geometric patterns and designs in the palaces of
Mitla and the cruciform structure of Guirún that suggests almost a form of
writing or a mathematical code, whose true meaning may however always escape
us.
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| A close-up view of some of the geometric patterns in the interior of the cruciform structure of Guirún. Were these intricate pattners carved or molded on the stone? [Photo by Author] |
The ruins of the valley of Tlacolula and Mitla represent a
unique example of megalithic architecture displaying a workmanship and a
tendency towards monumentality unknown in the rest of Mesoamerica. These
magnificent structures appear as if out of nowhere, and are the expression of a
tradition of working in stone that had already become extinct long before the
time of the Spanish conquest.
References
[1] Toribio
de Benavente Motolinia (1482-1568), Historia
de los Indios de la Nueva España
[2] Francisco
de Burgoa, Geográfica Descripción,
1674
[3] Marshall H. Saville, The
Cruciform Structures of Mitla and Vicinity, Putnam, 1909
[4] Gary M. Feinman and Lind M. Nicholas, Hilltop Terrace Sites of Oaxaca: Intensive
Surface Survey at Guirún, El Palmillo and the Mitla Fortress, Field Museum
of Natural History, Chicago, 2004
[5] Nelly
M. Robles Garcia, Las Canteras de Mitla,
Vanderbilt University, 1994, pp. 17-19
[6] V. H. Garduño-Monroy, et al., The Mitla Landslide: An event that changed the fate of a Mixteco/
Zapoteco Civilization in Mesoamerica, International Journal of Geophysics,
vol. 2019, https://doi.org/10.1155/2019/5438381
Note: All the pictures on this page are intended for non-commercial use only and may be reproduced on other websites or publications so long as the source is cited. Exploration of the site was conducted with the help of certified guides to ensure the preservation of archaeological remains and the natural environment.