The ancient city of Machu Picchu is a magnificent architectural masterpiece, perched on a mountainside at an elevation of over 2,300 meters, resembling a city floating in the clouds.
Machu Picchu was built over 500 years ago and, even in a region prone to earthquakes, it still stands strong. What’s even more remarkable is that the stones here are stacked together so perfectly that it is hard to believe, with not even an ATM card able to fit between the stones.
This raises the question: How did the Incas manage to construct such a large-scale city? The people of that time lacked stone-cutting tools, modern construction machinery, and contemporary transportation methods—how did they transport the massive stones to the mountaintop and assemble them with such precision?
Machu Picchu is an ancient city built between the Andes mountains and the Amazon rainforest in Peru. Like a forgotten piece of history, it wasn’t until 1911 that Machu Picchu was rediscovered, and fortunately, it has remained well-preserved with many remnants of the Inca civilization still intact.
In the past, there existed a mysterious country in ancient South America known as the Inca Empire, which emerged around the 11th century AD. This nation was highly developed compared to its contemporaries and achieved significant advancements in astronomy and history.
However, the Inca Empire is also shrouded in mystery as it is the only major civilization at that time without a written language. Due to the lack of written records, the history of the Inca Empire remains an enigma. Most of what we know about the Inca Empire today comes from the writings of the Spanish, who invaded the area to plunder and conquer the ancient Inca civilization.
Although this ancient empire has long vanished, it left behind a mysterious site: Machu Picchu. This city is often referred to as the “Lost City of the Incas” because it was not discovered or destroyed during the Spanish conquest of Peru.
It wasn’t until 1911 that American historian Hiram Bingham, while searching for the capital of the Inca Empire, discovered this city that had been hidden away on a mountain top at an elevation of over 2,300 meters.
Archaeological evidence, along with recent studies of early colonial texts, indicates that Machu Picchu was not an ordinary city but rather a resort town for Inca nobility. Machu Picchu was designated a UNESCO World Heritage Site in 1983 and recognized as one of the New Seven Wonders of the World in 2007.
First and foremost, we must highlight the construction techniques of the Incas. The stones throughout the ruins of Machu Picchu, regardless of their size, fit together seamlessly. The joints between the stones are crafted so well, they appear almost unbelievable.
The city is believed to be able to withstand major earthquakes of 9 degrees on the Richter scale or higher. Considering that Peru is located on the Pacific Ring of Fire and frequently experiences earthquakes, the fact that Machu Picchu has stood at an elevation of over 2,300 meters for more than 500 years is a testament to the exquisite architectural skills of the ancient Incas.
Additionally, the arrangement of the stone blocks in Machu Picchu follows unique rules. The larger stones at the bottom are generally irregularly shaped. It is said that this arrangement could increase the surface area during shaking in an earthquake, thereby dispersing forces in different directions and minimizing earthquake damage.
Inca houses are constructed from smoothly polished stones, tightly fitted together without the use of mortar. As a result, each house varies in size and shape.
The foundation of Machu Picchu is one of the crucial reasons it can remain standing. The area has a humid climate with heavy rainfall, making it prone to landslides. To stabilize the mountainside, the ancient Incas devised a method known as terracing.
This design not only addresses drainage issues but also stabilizes the overall structure. The angle of the stone walls is precisely five degrees, which is a stable angle that can transfer most of the weight down to the ground. The terracing structure is divided into three layers: the top layer is soil, the second layer is sand, and the bottom layer consists of larger stones and gravel.
One advantage of this design is that after rain, water can quickly seep into the ground rather than flowing down the hillside, thus preventing landslides. However, such a technique was evidently very challenging for ancient people. How did they accomplish this without measuring tools and extensive knowledge? Beyond the profound design considerations, shaping the stones into various forms is even more difficult.
The stone blocks in the major structures also have sloping surfaces that interlock to resist earthquakes, allowing them to endure even after many historical upheavals.
Experts have discovered that the hardness of these stones is six on the Mohs scale, while copper and iron are rated at three and four, respectively. This indicates that the hardness of copper and iron is inferior to that of the stones at Machu Picchu, suggesting that the shaping of these stones could not have been achieved using tools made of iron or copper.
Therefore, it is speculated that the stones at Machu Picchu were shaped by striking stone against stone, but clearly, stone tools could not smooth them out to such an extent, as the stones would undoubtedly crack in the process. Thus, the builders must have possessed highly advanced skills to shape the stones and make them smooth.
So, who truly built this entire city? Despite many years of exploration and research, little is known about the history of this city and its builders. Initially, it was believed that the city was constructed by the Inca civilization due to its architectural style resembling that of the Incas, but upon further investigation, doubts began to arise regarding this claim.
Firstly, the technical capabilities of the Inca civilization at that time were not sufficient to construct such a large-scale city, and the architectural style here differs in many respects from that of the Inca civilization. Furthermore, the manner in which the large stones and smaller gravel are stacked also suggests that the city may have been built by two different groups of people.
Reaching Machu Picchu is not a simple journey. There are no buses or trains that go directly from the city to here.
It is speculated that after the initial builders left, the Inca civilization arrived and continued to expand the city. Evidence from the nearby city of Cusco shows that after the Spanish occupation in 1532, many new houses were built. However, every time a major earthquake occurred, their houses would collapse, while the architectural foundations of this city remained unaffected. Even the buildings constructed by local people today are often destroyed by earthquakes, and this may serve as clearer evidence of the extraordinary construction skills of the city’s builders. So, who were these builders with exceptional architectural skills?
As recently as 2012, a stone gateway was discovered at Machu Picchu, seemingly blocked off by later generations. Some experts used metal detectors to investigate and discovered that there was a metallic substance in the door, which sparked significant interest.
Some speculate that the secrets of the builders may be buried here, but the Peruvian government has refused to allow access to open the door, fearing that removing the stones could cause a collapse and damage the overall structure of Machu Picchu.
Who the builders of Machu Picchu were and how they constructed it remains a mystery. How could a civilization without written language, wheels, and iron create such a marvelous city?
