Machu Picchu: The City in the Sky

What is Machu Picchu?

Machu Picchu is an ancient Inca city perched high in the Andes Mountains of Peru, rising 2,430 meters above sea level in a lush tropical mountain forest. 

Within its stone walls are 170 buildings, each showcasing astonishing craftsmanship. When construction began around 1450 CE, builders shaped stones with such precision and fitted them so tightly that not even a piece of paper could slip between the joints. As a result, the site has withstood earthquakes and extreme weather for nearly 600 years.

Perhaps even more impressive is that around 60% of the work lies hidden beneath the surface—deep foundations with tonnes of crushed rock allowing drainage of flood waters and heavy rainfall. Much of Machu Picchu’s brilliance is invisible to the eye but vital to its lasting stability.

There is also a pyramid built from layered terraces stacked like the tiers of a wedding cake. At its peak stands the Intihuatana, a large stone functioning as a type of sundial. This ancient instrument aligns with the nearby peak of Huayna Picchu during the summer and winter solstices, revealing the Incas' profound understanding of astronomy.

Who built it, and why?

Machu Picchu was constructed during the reign of the Incan Emperor Pachacuti (Pachacútec) in the 15th century. Radiocarbon dating suggests that the area in which it was built was occupied from roughly 1420 to 1532.

Scholars have proposed numerous theories about the site's purpose. Some have argued it was a prison or a ceremonial site for royal coronations, while others speculate it functioned as a trading hub for crops like potatoes and quinoa, both native to Peru.

One unlikely theory suggests that Machu Picchu was a physical manifestation of the Incan creation myth. 

The most plausible explanation, however, is that it served as a royal retreat—a peaceful escape for the Incan elite from the bustling capital city of Cusco. Set amongst the clouds and lush vegetation, the site would’ve been fit for a king.

The exuberance, the colours, the fruits, new crops, new flavours—it was so attractive that I think it makes complete sense to build this display of power and put your royal family at the very frontier of this place.

Javier Puente, historian of the Andes and an associate professor of Latin American studies at Smith College in Massachusetts

Why was Machu Picchu abandoned?

In the 1520s, the Incan civilisation was devastated by smallpox, a disease brought to South America by Europeans. Although no reliable records exist, it is estimated that European diseases wiped out around 90% of the indigenous population across the Americas over the remainder of the 16th century.

When Spanish explorer Francisco Pizarro arrived in Peru in 1526, the Incan Empire was in disarray: crippled by a deadly pandemic and torn apart by internal conflict, particularly a civil war between rival heirs to the throne. Seizing the opportunity, the conquistadors—led by Pizarro—were able to conquer an empire the size of Spain with a force of just 168 men.

Amid this chaos, Machu Picchu was largely abandoned. The once-thriving city, which had stood as a symbol of Incan power and ingenuity for over a century, was left to the jungle.

When did it become a global sensation? 

On July 24th, 1911, American professor Hiram Bingham III arrived in Peru on a quest to find the legendary Lost City of the Incas. While there, a local boy led him up the mountain to Machu Picchu. At first, Bingham was underwhelmed—where were the ancient treasures and the Mayan-like temples he had imagined?

Later on the same trip, Bingham did rediscover the last stronghold of the Incas in an area called Vilcabamba, some 25 miles up river. But something about Machu Picchu had captivated him. A year later, Bingham returned, taking photographs and detailing his experiences.

It seemed like an unbelievable dream. Surprise followed surprise in bewildering succession. 

Hiram Bingham III

Bingham's incredible images and vivid storytelling struck a chord with the public, and National Geographic dedicated an entire issue to his findings. His account sparked global fascination with the Incas, and Machu Picchu soon became a magnet for explorers and tourists alike. Today, the site attracts over half a million visitors each year.