How a proto-Indiana Jones rediscovered the Inca stronghold of Machu Picchu

Then, “suddenly I found myself confronted with the walls of ruined houses built of the finest quality of Inca stonework”.

He had discovered the long-lost Inca city of Machu Picchu, and – though he couldn’t have known it at the time – it was to prove one of the greatest archaeological discoveries of the 20th century.

Hiram Bingham III is sometimes hailed as a kind of proto-Indiana Jones – a buccaneering archaeologist-turned-adventurer who felt more at home in the middle of a jungle than buried in a textbook. He developed a passion for Latin American history as a boy and, armed with a PhD in the subject, made the journey to Yale University to pursue a career as a lecturer. He might have stayed at Yale, had he not met and married Alfreda Mitchell, an heiress to the Tiffany jewellery fortune. Bingham now had the financial security to fulfil his dream – embark on his first expedition to South America.

That first adventure, in 1906, saw him trace the celebrated political leader Simón Bolívar’s routes through Venezuela and Colombia in 1819. But it was a people who dominated South America 300 years before Bolívar who really fired Bingham’s imagination, and ultimately led him to that first, historic sighting of Machu Picchu. They were the Inca.

Who was Hiram Bingham?

If Hiram Bingham III’s parents – both missionaries – had gotten their way, then instead of stomping around Peru in search of Inca cities, their son would have carved out a living spreading the word of God.

But Bingham was more interested in South American history than the scriptures. And so he embarked on a series of expeditions to Peru in search of long-lost Inca cities.

Following his landmark discovery of Machu Picchu in 1911, Bingham went into politics, serving as a member of the US Senate for the state of Connecticut and, later, helping President Truman’s administration identify communists working in government. He died in 1956.

Why was Machu Picchu abandoned?

Over the course of a few hundred years from the 12th century AD, the Inca forged one of the greatest empires the world had yet seen. They were warriors, conquerors, architects and road-builders extraordinaire, presiding over a vast swathe of territory that ran 2,500 miles down South America’s western seaboard. Unfortunately for them, however, they also developed an obsession with gold.

For in 1532, a ruthless Spanish conquistador named Francisco Pizarro stepped onto Inca territory, accompanied by around 180 followers. Pizarro shared the Inca’s infatuation and, hearing tales of their vast and exquisite stores of yellow metal, made a beeline for their emperor, Atahualpa.

In the long, and sometimes undistinguished history of European colonialism, what happened next has gone down in infamy.

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In November 1532, Pizarro invited Atahualpa to a meeting in the town of Cajamarca. But the conquistador had a nasty surprise for his host. Having lured Atahualpa and his followers into a plaza, Pizarro’s men attacked, unleashing volleys of gunfire into the unarmed Inca masses. Many were killed and Atahualpa was taken hostage.

To earn his freedom, the emperor reportedly offered Pizarro a ransom that would make the conquistador fantastically rich – a room full of gold, and two full of silver. Almost immediately, gold started pouring in from across the Inca empire. But the Spanish reneged on their promise to release Atahualpa, and instead had him executed.

It was an act that triggered all-out war; a triumph of military technology over weight of numbers. The Spanish could only call upon a couple of hundred men – far fewer than the thousands that the Inca had at their disposal. But what the Spanish did possess was armour, firearms, cannons and horses. Against an enemy that possessed clubs and spears – and which had already been weakened by civil war and smallpox – these were to prove decisive.

Within a few short years, the Spanish had utterly ravaged the once-great Inca empire, levelling towns and temples wherever they found them. And it was what happened as Pizarro and his men slowly but surely squeezed the life out of Inca resistance over the following decades that brought Hiram Bingham III back to Peru on another expedition in 1911.

When did Hiram Bingham find Machu Picchu?

What drew Bingham to South America was the long-lost Inca citadel of Vilcabamba. It was from here, deep in Peru’s mountains, that the emperor Manco Inca had led an audacious guerrilla campaign against the Spanish. And it was here that the very last embers of Inca resistance were extinguished in 1572.

Bingham was determined to find this tragic city. The thrilling possibility that he had done just that must have raced around his head as he explored Machu Picchu for the first time in July 1911. But this wasn’t Vilcabamba; it was somewhere far more spectacular still.

Bingham would return to Machu Picchu on numerous occasions over the following years. He took hundreds of photographs, excavated scores of graves, and transported thousands of objects – among them pottery, tools and bronze knives – back to the United States (in doing so, he sparked a longrunning spat between Yale and the Peruvian government, which accused the university of profiting from Peru’s cultural heritage).

But it was what Bingham left behind him that led UNESCO, when appointing Machu Picchu a World Heritage Site in 1983, to declare it “an absolute masterpiece of architecture and a unique testimony to the Inca civilisation”.

Archaeologists believe that somewhere between 300 and 1,000 people lived up here in the city’s heyday. As subsequent excavations would reveal, the city was divided between an agricultural and an urban sector, the latter made up of major temples, housing and workshops, and an open central plaza where the population would have congregated to worship. And, as Bingham soon realised, these were no ordinary buildings – they were masterpieces of engineering, edifices of almost mind-boggling beauty and complexity.

They may have had nothing more than stone and bronze tools at their disposal, but Inca craftsmen were masters of their art, constructing the walls and buildings that sit atop Machu Picchu with almost surgical precision.

Of these, none is more impressive than the Temple of the Sun, a huge, semicircular place of worship aligned to catch the Sun’s rays on the winter solstice. It was constructed around what the Inca would have regarded as a sacred rock, which may have acted as an altar.

Worship of the Sun God was clearly important to the residents of Machu Picchu, and this is borne out by the presence of a famous ritual stone known as the ‘Inti Watana’. Archaeologists believe that the Inca performed a ritual here at winter solstice, in which they ceremonially tied the Sun to the post so that it couldn’t fall permanently below the horizon.

If the Temple of the Sun and the Inti Watana were the spiritual hubs of Machu Picchu, then a series of exquisite buildings containing a royal palace – known as the ‘king’s group’ – appear to be the secular centre. This was clearly the residence of someone very important, for not only is it the most elaborate of Machu Picchu’s buildings, it was also sited next to the city’s most impressive fountain, serving up water delivered by a 760-metre-long stonelined canal.

If that was an amazing hydraulic achievement, then the city’s famous terrace system was perhaps even more impressive. Twelve acres of fertile farming land provided maize, potatoes and even avocados for the population’s palates. And, by soaking up the 2,000 millimetres of rainfall that fell from the sky each year, the terraces would have served another critical purpose: stopping the city from sliding off the side of the mountain.

Why was Machu Picchu built?

To appreciate the true genius of Machu Picchu, you have to consider not just what it contains, but where it is: 2,430 metres above sea level; 450 metres above the river Urubamba, which races past the feet of the cliffs below.

This truly is a city in the clouds, and the fact that its inhabitants had to transport 20-tonne stones up the side of this mountain with perhaps nothing more sophisticated at their disposal than wooden sleds turns it from a spectacular engineering achievement into an astounding one.

But the question is, who was the driving force behind this awesome achievement, and why did he or she have it built? It was a question that Bingham took to the grave. Now, 60 years after the great adventurer breathed his last, we appear to have an answer.

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The breakthrough came when University of California, Berkeley, anthropologist John Rowe discovered an Inca document that contained references to a royal retreat called ‘Picchu’. That document also made mention of a legal claim to ownership of ‘Picchu’, laid down by descendants of Emperor Pachacuti. The inference is clear: if the emperor’s successors were claiming Machu Picchu as their own, then it must have once been his. The theory that Pachacuti ordered the building of Machu Picchu (in around 1450) has proved persuasive.

As a fearsome warrior-leader who presided over the Inca empire at its very height, he certainly had the power to assemble the most talented people and the unlimited labour that would have been required to attempt such a massive undertaking.

What has also proved persuasive is the suggestion that Machu Picchu was a royal retreat where the emperor and his closest advisers would have repaired each winter when the climatic conditions in his capital city, Cusco (at an even more dizzying altitude of 3,400 metres), became too harsh. This elite party may have entered the city via a secret, grass rope-bridge over the river at its base before taking up residence at Machu Picchu’s impressive royal palace.

Why was Machu Picchu abandoned?

Machu Picchu outlived its probable creator – who died in 1471 – but not by much. Pizarro's men never discovered the site but, a decade after they deceived the unsuspecting Atuahalpa in 1532, its residents were gone.

Perhaps they felt isolated up there in their lofty home, perhaps they didn't have enough supplies to sustain themselves. Either way, they left it to be swallowed up by the Peruvian forest, where it lay largely forgotten, until Bingham stumbled across it more than 350 years later.

Today, Machu Picchu is anything but forgotten – hundreds of thousands of tourists visit it every year. Like Pachacuti and Hiram Bingham III before them, these visitors have to make an arduous journey up the mountain. But, within seconds of casting their eyes on this wonder of the world, they surely know that their effort was worth it.

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This content first appeared in the January 2017 edition of BBC History Revealed