Sunday, October 1, 2017

Mysterious geoglyphs and a new pyramid at Teotihuacan?

New elements in the astronomical design of the site
The Cerro Colorado, as seen from the Pyramid of the Sun. [Courtesy: Google Earth]
The reason for Teotihuacan’s orientation 15.5° East of North has been one of the most enduring mysteries of Mesoamerican archaeology. The only answers so far have come from natural topography. The summit of the Cerro Gordo mountain, to the North-East of Teotihuacan, appears to be aligned to the Pyramid of the Sun if a perpendicular is drawn through its Northern face (Contrary to common belief, the Avenue of the Dead does not point toward the summit of the Cerro Gordo, but rather to a point slightly to the West of it). One nearby summit, the Cerro Colorado Chico, however significantly stands out for its apparent exclusion from the system of topographical alignments that characterize the ancient site. 
The Valley of Teotihuacan, as seen from the summit of the Cerro Gordo, looking South. The Cerro Colorado lies to the right in the picture, with the Patlacique Range in the background along the axis of the Avenue of the Dead. [Courtesy: Google Earth]
This is even more surprising if one considers that the Cerro Colorado is the most prominent elevation in the immediate vicinities of Teotihuacan besides the Cerro Gordo to the North and the Cerro Patlacique to the South. Because the Cerro Colorado is located due West of Teotihuacan, this would make it an excellent, and indeed the only possible natural sunset solsticial marker for an observer located on top of the Pyramid of the Sun. 

As a first step, we set out to investigate the astronomical angles of this alignment: 

  • Cerro Colorado Azimuth from Sun Pyramid: 301.91°
  • Distance from Sun Pyramid (summit-to-summit): 4.17Kms
  • Difference in elevation between Sun Pyramid and Cerro Colorado (summit-to-summit): 240m
  • Angle between Sun Pyramid and summit of Cerro Colorado: 3.294° (calculated)
Because the present Azimuth of the Summer Solstice sunset as observed from Teotihuacan is only 293.5°, the Sun would set some 8.41° to the South of the summit of Cerro Colorado, at a point near its base. 

We then focused on the Moon Pyramid instead, with the following readings:

  • Cerro Colorado Azimuth from Moon Pyramid: 291.64°
  • Distance from Moon Pyramid (summit-to-summit): 3.77Kms
  • Difference in elevation between Moon Pyramid and Cerro Colorado (summit-to-summit): 246m
  • Angle between Moon Pyramid and summit of Cerro Colorado: 3.733° (calculated)
The observed Azimuth of 291.64° is much closer to the target 293.5° (the difference being less than ), which would make the Cerro Colorado a fairly accurate solsticial marker for an observer located on the summit of the Moon Pyramid at sunset. 

The Summer Solstice sunset as seen from the top of the Pyramid of the Moon [Courtesy: Google Earth]
Geoglyphs and a possible pyramid

We explored the summit of the Cerro Colorado using Google Earth in search of possible ancient structures that could have served as astronomical markers to validate the alignment. To our surprise, the images revealed what appears to be a pyramid platform located on top of the mountain, at an altitude of 2,597 meters above sea level. The pyramid measures an apparent 10 meters on each side, consists of two or possibly three superimposed bodies and has what appears to be a stairway facing to the South-East. Interestingly, a line drawn through this stairway points directly towards the summit of the Pyramid of the Sun.  
The location of the possible Pyramid on top of the Cerro Colorado. The building is precisely aligned towards the Pyramid of the Sun, some 4 kilometers away. [Courtesy: Google Earth]
Immediately below the “pyramid”, we also identified an immense geoglyph, measuring over 150 meters in length, also facing the valley and the Pyramid of Teotihuacan to the South-East. The geoglyph consists of three squares delimited by what appear to be dry-stone walls, each containing a glyph and a number of abstract symbols. The rightmost quadrant contains a “X” shape with symbols in the upper and lower portion (the one below resembling the letter “S”). The glyphs in the center and leftmost quadrant are of more difficult interpretation. 
A view of the geoglyphs near the summit of the Cerro Colorado [Courtesy: Google Earth]
There seems to be no mention of structures (either ancient or modern) near the summit of the Cerro Colorado, nor of geoglyphs on its slopes. Even though it is possible that the geoglyphs are of modern origin (drawn by whom and why?), the location of the “pyramid” on the summit of the Cerro Colorado and its alignment to the Sun Pyramid are certainly interesting in light of its possible astronomical significance. 

Only an expedition on the ground can solve the question of whether these are indeed ancient structures and their relationship to the nearby Teotihuacan pyramids. 


  1. It appears your promising find on top of Cerro Colorado is modern in origin. The pyramid appears to be a radio antenna tower which, admittedly, from above looks a lot like a pyramidal structure. However the dark line extending NE from the structure is the tower's shadow which shows it's quite tall and narrow. Scrolling back in time through Google's imagery of the site reveals different views of this tower that makes it's nature fairly apparent. Could it be built on top of an ancient platform? Maybe? The alignment is awfully suspicious.

    And the geoglyphs appear to be aerial markers for military pilots. There's a particularly good shot of them in the 6/12/2002 Google Earth dataset where they stand out bright white against the ground. I have no idea what they mean, but they do look very similar to other military iconography I've seen.

    Keep on exploring, I love your blog!

    1. Thank you, Calenlas!
      It turns out that the supposed geoglyphs are indeed of modern origin. The symbols are those of a military artillery regiment stationed near Teotihuacan.
      Unfortunately the apparent platform located on the mountaintop lies within a restricted military area, so it is not possible to ascertain whether it is also of modern or ancient construction. I was also intrigued by the shadow and thought at first that it must be the base of a communication antenna, however I have checked with binoculars during my last visit at Teotihuacan and there is no such thing as an antenna (nor anything visible from a distance, truly) on top of the Cerro Colorado. If there was ever an antenna there maybe it's been removed?