The 13 Towers – Chankillo, Perú
As the predictive ability of utilizing the sunrise or sunset on the horizon became more sophisticated, astronomers, architects, engineers and artists began to create earthworks, sculptural devices and edifices as monuments to their knowledge. However, with many sites mysteriously abandoned and with little written record, contemporary archaeoastronomers have taken up the challenge of rediscovering how those calendars work.
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| Latitude: 9º 40′ S | Longitude: 78º 13′ W | |
How does a Horizon Calendar Work?
Chankillo is believed to be the oldest solar observatory in the Americas. It dates back 2500 years, is located near the desert coast of Perú, and predates the Inca by 2000 years. Professors Ghezzi, Ruggles and Aveni have all verified that the 13 towers cover the entire solar arc, and are aligned on a north / south meridian. This means that the ancient civilization could have regulated a calendar by keeping track of the number of days it took for the sun to move from tower to tower.
In the photo above you can see the sun rising between the stone towers that correspond with the zenith sun, which is only viewed between the tropics, latitudes 23.5º north and south of the equator. The towers also help mark other solar events and count out the 10-day week (30 day month) used by Andean cultures.
The photo below shows the sunrise alignments of the solstices and equinoxes as viewed from the western observation point as calculated for 400BC during the solstices.
Position of sun (above) in yearly cycle compared to how it appears at Chankillo (below)
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| View of towers from north east | Towers are over 15′ tall |
HOW DID I HAPPEN TO GET THERE?
I was captivated from the moment I first saw the defining desert image of this intriguing architectural landform. It was challenging to get to this site. After a six-hour trip we managed to locate a rare guide who was willing to take us in. Two hours later we were hiking down into this remote desert valley — much easier getting in than climbing out. I went back again the next morning for the distinct privilege of a solitary “no sign of human life” sunrise.