How Machu Picchu Was Built: The Genius Behind the Stone

Alberto Chang Chirinos
11 jun
5 Min. de lectura

Actualizado: 1 sept

First time at Machu Picchu for everyone except my dad, who went about five times on school trips. I had just been admitted to UC Berkeley, so we wore our Cal shirts to celebrate.

If you’ve ever seen an image of Machu Picchu, you’ve probably wondered the same thing millions of people around the world have: how was it possible to build something so impressive, so precise, and so harmonious with nature… more than 500 years ago?

Machu Picchu is much more than a spectacular postcard. It is a silent testament to a people who knew how to read the land, move mountains without modern machinery, and design a city that still functions today.

First, the Perfect Location

Machu Picchu is situated on a mountain ridge between two peaks: Machu Picchu (“old mountain”) and Huayna Picchu (“young mountain”). This location was not chosen by chance. From there, you can oversee the Urubamba valleys, observe the movements of the sun and stars, and be protected from natural disasters like landslides or floods. For the Incas, building in that place was a way to get closer to the cosmos while staying in harmony with the earth.

Cusco, the capital of the Inca Empire. At 3,399 m above sea level, the thin air was already noticeable, but soon I'd have coca tea to help me acclimatize.

With my parents in front of an Inca religious center in Cusco, 75 km from Machu Picchu. The stones were carved with copper and stone tools to fit perfectly without mortar.

Water as the Silent Architect

One of Machu Picchu’s greatest technical achievements is its hydraulic system. The Inca engineers discovered a natural spring on the northern slope and built a stone canal that distributes water throughout the city. This aqueduct not only supplied fountains and homes but also prevented flooding by channeling water in a controlled way. Remarkably, part of this system still works more than 500 years later without metal pipes, pumps, or modern concrete.

Kissing a llama on the streets of Cusco, while its herder (cholito) was asking for tips. — Kissing a llama on the streets of Cusco, while its herder (*cholito*) was asking for tips.

Walls That Speak of Precision

The most important structures at Machu Picchu — such as the temples and elite residences — are made with polished stones that fit together without the need for mortar. This technique, known as “ashlar”, was not only aesthetic; it allowed the walls to withstand earthquakes. In a seismic zone like the Andes, that’s high-level engineering. But it wasn’t all monumental. There are simple yet significant details: many windows are exactly the length of a forearm and are spaced apart by the same measure. It was a way to standardize without losing visual harmony, revealing the precision and aesthetic sense of the Inca builders.

Terraces That Support and Sustain

Around the city, the Incas built stepped terraces that served to grow crops, control erosion, and stabilize the land. These platforms are key to understanding why Machu Picchu still stands: they not only supported agriculture but also functioned as an intelligent drainage system that kept the soil firm even during heavy rains.

Nothing Was Improvised

Machu Picchu looks like a natural city as if it had sprung from the mountain. But, in reality, it was a meticulously planned urban project. The roads, temples, homes, and agricultural areas are all laid out with logic and purpose. In fact, more than half of the construction work is not visible as it lies underground. Deep foundations, hidden drainage systems, and carefully compacted fill ensure the city’s stability. The Incas knew that to build something lasting, you had to start with what’s invisible.

Locals in Ollantaytambo preparing to celebrate the Bajada de los Reyes Magos, one of the many living traditions of the Sacred Valley. — Locals in Ollantaytambo preparing to celebrate the *Bajada de los Reyes Magos*, one of the many living traditions of the Sacred Valley.

And Why Build Machu Picchu?

There is still no absolute consensus among historians, but all evidence points to Machu Picchu being much more than a city: it was a spiritual, political, and astronomical center for the Inca elite. Some believe it was a royal residence for Emperor Pachacútec, others think it served as a sacred sanctuary where heaven and earth connected. What is certain is that its location, architecture, and orientation respond not only to practical needs but also to a worldview in which every stone had a purpose and every architectural decision was also an offering to the gods, especially Pachamama, ("Mother Earth"), with whom the Incas sought to live in balance and reciprocity.

Machu Picchu’s terraces, temples, and water channels weren’t merely functional. They were designed to align with solstices, cardinal points, and sacred mountains. This deep connection to the cosmos speaks to an Andean philosophy in which time, nature, and spirit were inseparable. Building Machu Picchu atop a narrow ridge surrounded by the Urubamba River wasn’t a feat of showmanship, but rather an intentional act of reverence. The very act of construction was a ritual in itself, echoing the Inca belief that to shape the earth with harmony was to honor life.

The train I took from Ollantaytambo to Aguas Calientes, the gateway to Machu Picchu.

And So, How Did They Move Those Stones?

The largest blocks at Machu Picchu weigh up to 55 tons (that’s 110,000 lbs). No wheels, no pack animals, no steel tools. What they did have was knowledge: they used wooden levers, plant fiber ropes, and mud ramps to move and position the stones. The force wasn’t brute strength but rather collective and strategic.

And who did this monumental work? They were the mitmaqkuna (workers relocated from different regions of the empire) and hatun runa (common people of the Tahuantinsuyo), organized under the mita system: a form of mandatory labor that wasn’t slavery, but a temporary contribution to the state. In return, the Inca provided food, protection, and stability.

Inca leaders didn’t need punishments or chains to gather thousands of workers. The empire operated like a vast network of reciprocity: if you helped the Inca, the Inca helped you. Plus, participating in building a sacred place like Machu Picchu wasn’t just a civic duty but a spiritual one. For many, it was a way to honor the gods and ensure the world’s balance.

The Lost Roofs

Today we see the walls of Machu Picchu bare and exposed. But originally, the houses and temples had thatched roofs supported by wooden structures, many with designs that even surprised the Spanish chroniclers. Some compared them to the Pantheon in Rome because of the way they mastered the interior space. That part is lost, but imagining it whole gives us even greater admiration for its complexity.

The roofs, made of ichu grass tied over wooden beams, weren’t just practical: they were expertly engineered to withstand rain, wind, and time. Their steep angles allowed water to run off quickly during the wet season, while their lightweight materials kept pressure off the stone walls. Reconstructing them in our minds restores not just the missing silhouette of Machu Picchu, but also a glimpse into an Inca architecture that adapted to its surroundings and was always in dialogue with nature.

In Summary

Although much has been lost — the roofs, the sounds, the voices — what remains is enough to tell us a story of ingenuity, spirituality, and deep understanding of the environment. Machu Picchu still stands not only because of its stone, but because of the vision of those who placed it. And as long as it continues to spark questions, the mystery of the Incas will remain alive.