8 Unsolved Mysteries of Machu Picchu

By Google Arts & Culture

Words by Eric Esposito

By Dmitri KesselLIFE Photo Collection

Despite the fact that Machu Picchu was built over 500 years ago, with no mortar used to hold together its stones, and sits up a mountain — on an earthquake fault! — the city’s 500 stone buildings are, amazingly, still standing today. Located 50 miles from Cusco, Machu Picchu measures an incredible 116 square miles in the Peruvian Andes, some 7,900 feet above sea level.

By Frank ScherschelLIFE Photo Collection

What is Machu Picchu?

In 1911 Yale archeologist Hiram Bingham and a small team of seven set out to find the lost city of Vilcabamba, but would soon find themselves led to one of the most fascinating places the world had never known. On their way from Zuzco, the expedition team stumbled upon a local farmer by the name of Melchor Arteaga who told tales of the “old mountain” ruins known as Machu Picchu — this would soon prove to be the the “Lost City of the Incas”.

Dating back to at least the 14th century, it is now considered a Wonder of the Modern World. Even with the latest in 21st technology, scientists are baffled as to how Incas built this city without steel, mortar, or wheels. Below, we’ll explore eight similar mysteries and a few intriguing theories surrounding this sublime city in the clouds.

1. Who Called Machu Picchu Home?

Scholars can find no reference of Machu Picchu in Inca literature or folklore. So, a natural question arises: who actually lived in this city?

By Frank ScherschelLIFE Photo Collection

Although archeologists believe Machu Picchu could have supported a population of about 750, only about 200 skeletons have been discovered at the site. This low population number, along with the fact that many of the stone buildings appear to be religious abodes, has led some scholars to believe Machu Picchu was solely built for spiritual and ceremonial purposes, perhaps a city for the dead.

While there’s little doubt Machu Picchu served an important religious function, there are many other theories as to its use. Due to its proximity to Cusco, some archeologists contend this city was a retreat for nobles from the demands of city life.

Others scholars point to Machu Picchu’s terraces and suggest the Incas might have used Machu Picchu for more practical purposes like crop testing or as a trading hub.

There are even a few historians, referencing the cell-like area near the Temple of the Condor, that argue Machu Picchu might have been used as a prison. Who lived here and why? The jury’s still out.

Cranial Deformations in Machu Picchu by Inca cultureMuseo Machupicchu - Casa Concha

2. Why Are There Elongated Skulls at Machu Picchu?

As Bingham’s team unearthed about 100 skeletons on the Machu Picchu complex, they made a shocking discovery: some of the skulls were elongated. Archeologists have since discovered many of these elongated skulls in both Inca and Maya burial sites .

Deformed skull #2 by Inca cultureMuseo Machupicchu - Casa Concha

The common explanation for these odd shaped skulls is that they were formed using a binding technique. Since most of these skulls were discovered in cemeteries for nobles, it’s assumed Inca royalty made their heads artificially elongated to prove their dominance.

3. Sacred Site or Something More?

One of the most iconic buildings in Machu Picchu is the Temple of the Sun (aka Torreón). As the name suggests, archeologists believe this distinctive curved structure was used for religious ceremonies related to the sun god Inti. But how do we know?

This impressive building has a carved rock at the top that produces shadows corresponding exactly to the two solstices. For this reason, archeologists believe this temple was used both for rituals and astronomical study.

In addition to studying and praising the sun, the Torreón has a mysterious well-carved cave underneath. For a long time, it was believed this area served as a mausoleum for royalty. There are, however, many strange details in this cave (especially a stone staircase leading nowhere) that seem to suggest it was used for some other purpose which still remains a mystery…

4. How Did Incas Carry & Carve Granite?

Most of the granite rocks used in Machu Picchu’s construction weigh well over 50 pounds. Scholars still have no clue how people who didn’t have the technology of a wheel could have pushed these rocks up the steep Andean mountainside. The mainstream theory is, however, that hundreds of men must have worked together to push these rocks up the peak.

Plate by Inca cultureMuseo Machupicchu - Casa Concha

Even more impressive than the fact that the Incas got the rocks up Machu Picchu is that all of these stone structures were carved using the most primitive tools. Although the Incas lacked steel tools, they were somehow able to fit these stone so tightly together that it’s difficult to fit a piece of paper through them. This is why the buildings are still standing, despite being built at the top of a mountain on an earthquake fault line.

The latest theory for how the Incas got these stones to stick so tightly together is by using wet wooden wedges. As these wedges froze, it created fissures in the rocks that helped bind them together. This theory, however, doesn’t explain why the Incas sometimes carved huge structures out of single stones or how they were able to fit stones into strange patterns.

By Frank ScherschelLIFE Photo Collection

5. Did Aliens Help the Incas?

As noted above, most scholars discredit the notion that an alien race built or lived in the Inca empire. However, there are still many proponents of “astronaut theory,” which suggests Machu Picchu was built perhaps by a superior race, or at least an older and more advanced tribe.

Although it might sound outlandish, one of the astronaut theorists’ main arguments is quite interesting. Proponents of this theory often point out three distinct design techniques found throughout Machu Picchu. It’s usual to see heavy, finely carved stones on the bottom and then sloppy layers of small stones on the tops of many Machu Picchu buildings.

Andes, South America - Bolivia, Chile, Columbia (1947) by Dmitri KesselLIFE Photo Collection

While this theory is obviously far-fetched, it's based in very real questions for archaeologists. Why would a civilization regress in its architectural abilities with time? According to astronaut theorists, the older masonry on the bottom was from a superior civilization that predates the Incas.

6. Was The “Sacred Rock” Really Sacred?

Overlooking the mountain peak of Huayna Picchu in Machu Picchu’s northwestern region is an intricately carved stone known as the Roca Sagrada (Sacred Rock). Measuring over nine feet high on a 23-feet base, this stone impresses viewers due to the uncanny resemblance to the Cerro Pumasillo mountain backdrop. It is unclear why the rock formation would have been made to look like its background, or even if these silhouettes actually were purposefully made in such a fashion.

Andes, South America - Bolivia, Chile, Columbia (1947) by Dmitri KesselLIFE Photo Collection

In addition to its religious significance, there are theories that the Roca Sagrada might have served an important geographical function. Since this rock is located at the northern edge of the city, it could mark a path that goes between Machu Picchu and Huayna Picchu.

Detail of the Intihuatana stone (1971 - Printed in 1999) by Edward RanneyMALI, Museo de Arte de Lima

7. The Intihuatana Stone: Sundial or Heavenly Portal?

Another mysterious stone in Machu Picchu has been dubbed the Intihuatana. This name, which Bingham created from the local Quechua, means something like “place to bind the sun.”

Bingham chose this name because the shadow produced by the four-sided Intihuatana top matches perfectly with the March and September equinoxes. Most scholars believe the Intihuatana played a crucial role helping locals with agriculture. But was the Intihuatana really only a sophisticated sundial or did it serve a higher purpose?

A new theory put forward by archeologist Giulio Maglia has brought to light the mystery of Intihuatana once again, claiming that the stone may have served a more significant religious purpose. According to Magli’s theory, Machu Picchu was designed as the last leg on a pilgrimage that mimicked the Inca myth of a journey from the Island of the Sun into the stars. Magli believes the climb to the top would have been the final destination for pilgrims. The mystery, however, remains as to what exactly would have drawn pilgrims to such an impractical location so far from the river banks.

8. Why Did Machu Picchu Disappear?

Although scientists don’t know why or when Machu Picchu declined, most don’t believe it was a violent overthrow. All of the skeletons unearthed at this site show no signs of obvious physical trauma, and we have no records of Spanish conquistadors invading the region.

Mainstream historians blame smallpox, measles, and/or syphilis for Machu Picchu’s decline. The Spanish, who brought these diseases into Latin America, were close by in Cusco. If traders traveled into Machu Picchu, they could have brought the diseases with them.

Another theory about Machu Picchu’s decline was that it was getting too costly for the declining Inca Empire to finance. After suffering through civil wars, deadly epidemics, and the Spanish invasion, Inca royalty had bigger woes than keeping up Machu Picchu. In this theory, Machu Picchu’s population most likely fled to seek opportunities in other areas of the Inca Empire.

Inca Story, Peru (1946) by Frank ScherschelLIFE Photo Collection

Since there are no written records from European colonists or natives, experts can only guess as to how Machu Picchu was built and what purpose it served. That leaves us guessing too.

Machu Picchu
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