Thor Heyerdahl's hypothesis

In 1990, adventurer and publisher, Thor Heyerdahl, became aware of the "Canarian Pyramids" by reading an article written by Francisco Padrón in the Tenerife newspaper "Diario de Avisos" detailing "real pyramids on the Canaries".^[1] As Heyerdahl had hypothesized a transatlantic link between Egypt and Central America, he became intrigued by the Güímar pyramids and relocated to Tenerife. There Heyerdahl researched possible parallels between the Canarian terrace structures and pyramid structures in Egypt and Central America in pre-Columbian Mesoamerica as ceremonial areas.

Heyerdahl hypothesised that the Canarian pyramids formed a temporal and geographic stopping point on voyages between ancient Egypt and the Maya civilization, initiating a controversy in which historians, esoterics, archaeologists, astronomers, and those with a general interest in history took part.^[2][3]

Astronomical research and Freemasonry

In 1991, researchers of the Canary Institute of Astrophysics showed that the long sides of some of the structures at Güímar marked the direction of both solstices. The main limiting wall points to the sunset in the summer solstice and the pyramids have stairs on their western side which face the direction of the rising sun on the winter solstice. Also, standing on the platform of the largest pyramid on the day of the summer solstice it is possible to experience a double sunset, as first the sun sets behind a mountain top, then it emerges again from behind the mountain and sets a second time behind a neighbouring peak.^[4] However, it is impossible based solely on these observations to conclude what was the intention of the builders or the date of construction.^[5]

The researchers published a book in 2005 titled Las Pirámides de Güímar: mito y realidad (The Pyramids of Güímar: Myth and Reality), in which they suggest that the solstitial orientations of the pyramids were potentially motivated by Masonic symbolism. The authors argue that solstices are very important in the symbolism of Freemasonry, and that the owner of the land at the pyramids were built was himself a Freemason. This motivation would be only an aesthetic one and would not modify in any rate the fundamental motivation (agriculture) and date of construction.

Archaeological excavations

Between 1991 and 1998, archaeological excavations of the site were conducted by archaeologists of the University of La Laguna. Preliminary findings were presented at a colloquium in 1996, providing evidence for the dating of the pyramids.^[6] According to the preceding geophysical Georadar-Survey eight locations adjacent to the pyramids, each with an area of 25 m², were investigated in layers down to the solid lava-floor. In doing so it was possible to establish three specific sediment layers. Starting from the top these were:

1. A layer of thickness averaging 20 cm, consisting of humus-rich earth with many plant remains and roots; tracks from ploughing were clearly identifiable as were a broad spectrum of readily datable finds from the second half of the 20th century.
2. A layer of thickness averaging 25 cm, similar in composition to the first layer, however containing less humus and a larger amount of small stones; a large variety of finds which could be dated to the 19th and 20th century were found, of which an official seal from 1848 deserves particular mention.
3. A layer of thickness between 25 and 150 cm, composed out of small volcanic rocks, most likely put in place in one movement, which levelled the uneven stone underneath; the stones contained only very few finds, mostly a small number of pottery shards, of which some was local and some imported, both kinds were roughly estimated as belonging to the 19th century. The pyramids stand stratigraphically directly on top of this bottom layer, therefore allowing for an earliest date of construction of the pyramids within the 19th century.^[7]

Furthermore, under the border edge of one of the pyramids, a natural lava cave was discovered. It had been walled up and yielded artefacts from the time of the Guanches. Since the pyramids lie stratigraphically above the cave, the Guanche finds from between 600 and 1000 AD can only support conclusions on the date of human use of the cave. The above survey indicates that the pyramids themselves cannot be older than the 19th century.^[8]