Scientists are still confused how Machu Picchu was built

How did the Inca build Machu Picchu?

How did the Inca, a people without iron or steel, build a city that has withstood hundreds of years of earthquakes and inclement weather? Machu Picchu stands atop steep landslide prone slopes and active fault lines and gets up to 80 inches of rain...

Machu Picchu explained

High in the Andes Mountains, Machu Picchu stands as a testament to the ingenuity and resilience of the Inca Empire. Constructed in the mid-15th century during Emperor Pachacuti’s reign, this site is believed to have served as a royal retreat or ceremonial center. Its engineering marvels, including sophisticated aqueducts, terraced farming systems, and precisely carved stone structures like the Sun Temple, highlight the advanced skills of the Inca civilization.

Machu Picchu, 101

Machu Picchu was built right on top of two intersecting fault lines, which makes it even more baffling how its temples and terraces have survived for more than 500 years—especially since no mortar was used to hold the precisely cut stones together. As this three-minute NatGeo video explains, this ingenious construction method allows the stones to bounce in place when earthquakes hit, shaking and rattling but rarely collapsing.

Meet Pachacuti, the king who built Machu Picchu

In the 1400s, King Pachacuti of the Inca Empire wanted a summer resort for himself, his family, and his entourage. So he and his builders set out to build Machu Picchu, a feat of engineering, carving, construction, and more. Its 700 terraces remain intact today, while its trapezoidal stones inspire construction efforts around the world. Learn about the fascinating process of building this wonder of the world here.

The unsolved mysteries of Machu Picchu

Who lived there? How did they get all that granite up there? Who were the 100 bodies found buried here, and why did some of them have elongated heads? Explore eight of Machu Picchu’s unanswered questions while scrolling through panoramic, clickable street-view images of the site, in this guide from Google Arts and Culture.

Sacsayhuaman, the Inca's largest structure

Less well-known but arguably more impressive than Machu Picchu is Sacsayhuamán, a 15th-century fortress-temple on the outskirts of Cusco. The site also features huge stones—some weighing more than 100 tons—carved into interlocking blocks and joined together through mortarless masonry. Archaeologists estimate it must’ve taken some 20,000 laborers to complete construction. This video offers a clickable 3D virtual-reality tour of the site.

Machu Picchu before it was a tourist attraction

The Machu Picchu we know today is familiar thanks to its neatly manicured plazas, lovingly preserved stone buildings, and ever-present hordes of tourists. But that’s not what Hiram Bingham saw when Melchor Arteaga led him to the site in 1911. Back then, it lay covered by centuries of tropical overgrowth.

The US senator who found a city in the sky

Dr. Hiram Bingham, a Yale graduate and explorer, is credited with rediscovering Machu Picchu in 1911. Financially supported by his marriage to the Tiffany jewelry heiress, Bingham ventured into the Peruvian Andes in search of the lost Inca city of Vilcabamba. Instead, guided by local farmer Melchor Arteaga, he stumbled upon the awe-inspiring ruins of Machu Picchu.

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See how Stonehenge was built

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Why did the Spanish steal the Inca's mummies?

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The last Inca grass suspension bridge in Peru

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The ancient engineers inspiring modern building practices

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How the Inca used threads to communicate

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The Maya built their cities with advanced engineering

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Scientific advances have transformed understanding of Stonehenge’s builders

Techniques such as radiocarbon dating, DNA analysis, and isotopic testing have revised scholars' understanding of Stonehenge. This article presents evidence suggesting that societies were more cooperative and less violent than earlier theories had suggested.

Machu Picchu, sacred backdrop for your dating app pic

Anyone who’s been on Tinder or Hinge in the last decade has noticed it: the obligatory Machu Picchu selfie, almost as ubiquitous as those photos of men posing with a fresh-caught fish. How did Machu Picchu, of all places, become a dating-app cliche? This satirical essay from McSweeney’s doesn’t answer that question, but has a great time poking fun at it.

How 'the Iceman' got his tattoos remains a mystery

Ötzi the Iceman, discovered in 1991, is one of the oldest human mummies ever found—and his 61 tattoos remain a mystery. This explainer looks at how researchers believe the tattoos were made, what their placement suggests about ancient medicine and culture, and why we’re still piecing together their true purpose today.

The missing continent that took 375 years to find

It took scientists 375 years to discover the eighth continent of the world, which had been hiding in plain sight all along. But mysteries still remain.

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How to carry more than your own bodyweight

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The mysterious qualities of obsidian and magnetite

Obsidian is a dark volcanic glass created when lava cools quickly and frequently contains magnetite, a key early mineral used in compasses. Large deposits were discovered and used in central Mexico by the Toltecs roughly 1,000 years ago at the ancient site of Teotihuacan. This essay explores obsidian's cultural impact and the mysterious presence of magnetite in migratory birds.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

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The Washington Monument was completed in 1884 after nearly 40 years of delays and funding shortages

At the time of its completion, the Washington Monument stood as the tallest building in the world. Its construction stalled for decades due to political disagreements and the Civil War. The 555-foot obelisk cost nearly $1.2M to build (around $40M in today's dollars).

How do archaeologists know where to dig?

Archaeologists spend their days slowly uncovering buried artifacts, but how do they know where to look in the first place? New tech and old-fashioned shoe leather. Watch this five-minute video to learn more.

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world

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