How did the Inca build Machu Picchu?

Scientists are still confused how Machu Picchu was built

Machu Picchu, the 15th-century Inca city high in the Andes, continues to fascinate experts with its mysteries. The methods used to transport and carve its massive stones—some weighing 15 tons—remain unclear. Theories range from hundreds of men dragging the stones to innovative techniques like using expanding wet wooden wedges for precision carving.

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.

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.

Machu Picchu is an ancient Incan citadel set high in the Andes Mountains in Peru, abandoned for centuries before its rediscovery in 1911.

Inca trail interactive map

Machu Picchu gets all the attention, but it’s definitely not the only Inca ruin in the area. Some dedicated trekkers opt to see the sites through a multi-day hike down the Inca Trail, which spans 26 miles from the Sacred Valley to Machu Picchu and reaches elevations as high as 13,800 feet above sea level. This 3D tour gives a sneak-preview of the ruins along the route, and the intense topography.

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.

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.

Mapping tourism at Machu Picchu

Only 750 people lived at Machu Picchu at its height, but today, almost ten times that number trample through its delicate plazas and agricultural terraces every day. This data visualization vividly illustrates the skyrocketing numbers of visitors to Machu Picchu over the decades, and highlights the risks of over tourism, including soil erosion and other environmental threats, and negative social and economic impacts.

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.

How the great city of Cusco came to be, according to the Inca

The chronicler Inka Garcilaso de la Vega recorded the origin story of the Inka (also spelled Inca) and the founding of Cusco, the capital of the society's great empire. Listen to the Inca origin story in this 4-minute video narrated by a child.

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.

Why did the Spanish steal the Inca's mummies?

From inside stone palaces and atop sacred mountaintops, the Inca dead continued to wield incredible power over the living. So much so that the Spanish confiscated them. Read more about the afterlife of these mummies here.

The Inca Empire: a timeline

When did the Inca Empire solidify into an empire? When was it invaded by the Spanish? What remains of it today? Click through this timeline to learn more.

What was the Great Inca Road?

In little more than 100 years, it grew from a small kingdom in the highlands of Peru to become the largest empire in the Americas. Read about the critical role played by the Great Inca Road.

A virtual reality experience of Machu Picchu

If you can’t make it to the Andes, this virtual-reality experience—created using 360-degree cameras, and 3D modeling and sound design—is the next best thing. It lets you explore all the site’s major landmarks, including the Sun Temple and the Temple of the Condor, while listening to the sound of the wind whipping through the ruins, birdsong, and audio commentaries from expert guides.

Human sacrifice in the Inca Empire

In the lands ruled by the Incas, mountain deities were well-respected and related summits were often selected as places for making the most important of all offerings — human sacrifices.

The last Inca grass suspension bridge in Peru

High in the Peruvian Andes, the aging Q’eswachaka bridge sags precariously over the Apurímac River. It has been built and rebuilt continuously for five centuries. Read more about it here.

The Maya built their cities with advanced engineering

Maya cities featured pyramids, palaces, causeways, ball courts, and water-management systems that were engineered to support large populations—often tens of thousands—without the use of metal tools, draft animals, or wheeled transport.

Watch the annual three-day revamp of the Q'eswachaka bridge

Rebuilt every year since the Inca empire, this bridge still is used today by locals who want to traverse the 120-foot-wide gorge that runs beneath it. This three-minute video shows just how much effort goes into its restoration.

The decline of the Inca Empire

The Inca Empire was awash with gold, and the Spanish knew it. So what happened next? Read this BBC article to learn what happened during the last days of the Inca Empire.

How the Inca used threads to communicate

One of the great mysteries of ancient Peru is that the Inca did not have a system of writing, but communicated with a system of strings tied with knots. This 4-minute video explores its possible uses.

What was it like to rebel against the Inca Empire?

The Inca Empire grew to its gargantuan size and became the largest empire in ancient Americas through conquest, annexation, and arranged marriage, approaches that didn't always go over well with locals. Watch this five-minute video to experience a...

The explorer who re-discovered Machu Picchu

If there was a real-life inspiration for Indiana Jones, it may well have been Hiram Bingham, the Yale University historian who set out to find the rumored “lost city” of the Inca. This short feature from the BBC’s History magazine explains how this son of missionaries brought international renown to the site and to himself. In the process, he sparked an international feud that would last more than a century.

Yale returns Inca artifacts to Peru

From the time he came upon Machu Picchu in 1911, Hiram Bingham began removing artifacts and human remains from the site and bringing them back to Yale University. Yale's Peabody Museum held them for 100 years, despite demands by the Peruvian government and the public that they be repatriated. Finally, in 2011, Yale returned thousands of items, including ceramics, jewelry and human skeletons.

Inti, the Sun God of the Inca

The Incas were polytheistic, worshiping many gods, but Inti was the most powerful one in the pantheon. He was the god of the sun and also ruled over agriculture, fertility, and war. Inti was mainly a benevolent deity, though the Inca believed that solar eclipses meant Inti wasn’t pleased. To appease him, the Inca gave sacrificial offerings including food, white llamas, and even human beings.

The ancient engineers inspiring modern building practices

Modern concrete structures need replacing every 50 to 100 years, so why are buildings by the Maya, ancient Rome, and ancient China still standing strong? This article details how scientists are looking into humanity's past for clues on how to craft long-lasting structures. Part of the problem is adopting old material recipes to hold up to modern demands.

The original article revealing Machu Picchu to the world

After first coming upon the ruins of Machu Picchu in 1911, Hiram Bingham’s subsequent expeditions were funded by Yale University, the Peruvian government, and $10,000 from a then-young National Geographic Society—in fact, it was the first archaeological grant that NatGeo ever issued. The magazine devoted its entire April 1913 issue, all 192 pages, to Bingham and his findings. You can read that issue in its entirety here.

Layers of minerals revealed by erosion give Vinicunca its distinct colorations

Located in Peru's Andean mountains, Rainbow Mountain is known for its vibrant colors, which result from layers of minerals such as clay, sandstone, argillite, and limonite exposed over millions of years by rain, snowfall, and strong winds.

The Inca's last stand against the Spanish

The Inca Emperor marched to meet the Spanish, expecting them to surrender. Spoiler: They didn't. Listen to this podcast episode to hear what led up to this moment and what happened next.

Why are ancient ruins underground?

When cities fall into disrepair, it's often easier to flatten what you can and build on top. This is why modern archaeologists frequently discover ruins underground, revealing generational layers of cities rebuilt over time. This video explores major examples of this principle, from ancient Troy to even modern Seattle.

The three theories explaining how the pyramids were built

There's no consensus over how the ancient monuments were built, and no blueprints left behind. But centuries of study have produced three competing theories: a simple, massive external ramp, a more complex internal ramp, or a highly sophisticated water elevator.

The evolution of Mexico City, from the Aztecs to today

The sprawling modern city situated in the Valley of Mexico began a millennium ago as an island in the middle of Lake Texcoco, connected to land through a series of causeways. Learn how the Aztecs built Tenochtitlan, how the Spaniards conquered it, why the lake disappeared, and more with this visually rich history and geography of a city of 9 million people.

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.

Rediscovering the Inca Empire

In 1991, anthropologist Johan Reinhard was trekking up the snowy face of a dormant volcano when he came face to face with the mummified remains of a teenager who had been sacrificed to the Incan gods centuries earlier. The story of “Juanita the Ice Maiden” is just one of the riveting tales featured in this four-part series from the popular podcast "History Hit".

Is the Inca maiden the world's best-preserved mummy?

Found atop a snowy peak in the Andes, this teen mummy is at least 500 years old. Watch this four-minute video to see the Inca maiden, a mummy so well-preserved that small details, such as her many braids, are clearly defined.

Stonehenge was built using giant wooden rollers and precisely carved tongue-and-groove joints to lock the stones in place.

This short animation shows how human beings managed to lug 30-ton stones over miles of prehistoric English countryside and stand them up The Stone Age engineering involved using giant wooden rollers and carving precisely interlocking tongue-and-groove joints to hold the heavy stones in place.

What llama beans can tell us about the Inca Empire

Fun fact: Llama bean is just another term for llama poop. Another fun fact: Scientists are using these beans and related microorganisms to learn more about the Inca Empire. Read this article to learn how.

A bird's eye view of Teotihuacan

Dubbed Teotihuacán or City of the Gods by the Mexica, this city was first inhabited in the 2nd century CE and ultimately became an important cultural landmark for the Aztec empire. Located roughly 30 miles north of Mexico City, contemporary ruins contain a 200-foot tall Pyramid of the Sun, ancient neighborhood grids, and more. Explore the city in this virtual helicopter tour.

See a 3D reconstruction of Tenochtitlan, the Aztec capital

Teotihuacán was already ancient when the Aztecs encountered it

By the time the Mexica reached Teotihuacán, the vast city had been abandoned for centuries. First settled around 400 BCE, the inhabitants developed monumental temples, canals, and a carefully planned urban grid centered on the Avenue of the Dead.

Engineering tall structures requires managing wind, earthquakes, and other destabilizing factors

Reinforced concrete, energy dampers, braced frames, flexible structures, and aerodynamic decks were among the methods implemented when building structures such as the Shanghai Tower, the Texas Super Skyscraper, and the South Rangitīkei Viaduct.

What were the Aztecs really like?

Does the society live up to its blood-thirsty stereotype? Archaeologist Eduardo Matos Moctezuma answers this question and more in this short article. Moctezuma was the principal excavator of the major Aztec archaeological site Templo Mayor in the 1970s. He shares how the culture grew from a combined emphasis on war and agriculture, and ruled one of the world's largest cities at the time.

Techniques to earthquake-proof a building include the use of counterweights, such as a massive column or pendulum, to dampen the impact of seismic activity and isolating a building's structure from its base.

The long history of an ancient Andean beer made from corn

And often chewed before brewed. From dank chicherias in small towns to gourmet big-city restaurants catering to tourists, the traditional fermented-corn beverage chicha is still being drunk throughout the Andes. Read more here.

The high-tech mechanisms of the Roman Colosseum

The Roman Colosseum is one of the most iconic amphitheaters in the world and still partially stands today. Aside from its sheer size, the arena was equipped with some of the most high-tech engineering from the classical world, including sophisticated lifts, a huge retractable awning, and an underground network of tunnels, elevators, and trapdoors.

The Aztec Empire ruled over 80,000 square miles of central Mexico for nearly a century—until a small band of Spanish conquistadors brought it down in 1521.

The Aztec capital of Tenochtitlan fell after a brutal 75-day siege.

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.

Tenochtitlan, the Aztec Venice of Mesoamerica

Tenochtitlan was the capital city of the Aztecs, founded around 1325 on an island in Lake Texcoco, in what is today Mexico. It was a major political, economic, and religious center until its destruction by the Spanish in 1521. This video explores the marvels of the city, which began as an island but grew via causeways and in-filled land and culminating in a North American Venice.

A Manhattan building doomed to collapse was saved in secret

After completing the Citicorp Center, its engineer realized that cost-cutting measures to use bolted instead of welded joints made the building vulnerable to collapse under quartering winds. For three months, crews worked in secret at night to reinforce the building under Project Serene.