The discovery of a mountain of silver (and a new way to extract it) transformed this remote Incan hamlet into the economic centre of Spain’s empire – larger than London, Milan or Seville. But then the silver ran out …

“For the powerful emperor, for the wise king, this lofty mountain of silver could conquer the world.” So read the engraving on an ornate shield sent by Spain’s King Felipe II in 1561 as a gift to the city of Potosí, in what is now southern Bolivia.

Felipe was all too aware of the vast riches hidden beneath this remote Andean settlement. The conquistadors may never have found El Dorado, but they did find a mound of silver so large it would turn an isolated Incan hamlet into the fourth largest city in the Christian world in just 70 years, fund the creation of the most advanced industrial complex of its era, and define economic fortunes from China to western Europe.

At its peak in the early 17th century, 160,000 native Peruvians, slaves from Africa and Spanish settlers lived in Potosí to work the mines around the city: a population larger than London, Milan or Seville at the time. In the rush to exploit the silver, the first Spanish colonisers occupied the locals’ homes, forgoing the typical colonial urban grid and constructing makeshift accommodation that evolved into a chaotic mismatch of extravagant villas and modest huts, punctuated by gambling houses, theatres, workshops and churches.

High in the dusty red mountains, the city was surrounded by 22 dams powering 140 mills that ground the silver ore before it was moulded into bars and sent to the first Spanish colonial mint in the Americas. The wealth attracted artists, academics, priests, prostitutes and traders, enticed by the Altiplano’s icy mysticism. “I am rich Potosí, treasure of the world, king of all mountains and envy of kings” read the city’s coat of arms, and the pieces of eight that flowed from it helped make Spain the global superpower of the period.

Facebook Twitter Pinterest ‘The mountain that eats men’: Potosí depicted in 1553. Illustration: Alamy

Potosí was “the first city of capitalism, for it supplied the primary ingredient of capitalism – money”, notes the author Jack Weatherford. “Potosí made the money that irrevocably changed the economic complexion of the world.”

The production of silver in the city exploded in the early 1570s after the discovery of a mercury amalgamation process to extract it from the mined ore, coupled with the imposition of a forced labour system known as the mita. Native Peruvians from hundreds of miles away were forced to travel to Potosí to labour in the mines, then given the back-breaking task of carrying the daily quota of 25 bags of silver ore, each weighing around 45kg, to the surface .

Temperature and humidity differences between the depths of the mine and the surface meant pneumonia and respiratory infections were rife, with one mining boss noting: “If 20 healthy Indians enter on Monday, half may emerge crippled on Saturday.”

The mita imposed by Viceroy Toledo in Alto Peru caused demographic collapse, earning the hill in Potosí a Quechua name meaning “the mountain that eats men”. Writing about a group of 7,000 native Peruvians – taken from their homes far away to work in the mines – one Spanish observer wrote: “Only some 2,000 people return: of the other 5,000, some die and others stay at Potosí or the nearby valleys because they have no cattle for the return journey.”

Potosí was the first city of capitalism, for it supplied the primary ingredient of capitalism – money Jack Weatherford

Alongside the mita, Toledo’s other reforms were the first serious attempt to organise this boom city. Marshland was drained to open up more space for construction, dividing Potosí into a Spanish and a local district, and creating an intricate system of dykes and drains to fill five artificial lagoons that fed the mills – an extraordinary feat of hydro-engineering that guaranteed a steady supply of silver.

The ore mined by the native workers and African slaves made many Spaniards exceedingly wealthy. Drunk on “the mere fumes of silver”, an author of the time noted that the city’s residents “nurtured such elevated thoughts” – exemplified by mining boss Domingo Beltran, who reportedly proclaimed himself to be among the world’s most important figures: “The Pope in Rome, the King in Spain, and Domingo Beltran in Potosí ...”

The city did not just prove fatal to the thousands who died in the mines. Despite Potosí’s flamboyance, it was plagued by murderous disputes between warring Spanish miners, natural disasters and the perils of living at 4,000m, where very little grows. The first Spanish boy to survive birth in Potosí was born in 1584, nearly 40 years after the city’s foundation; in 1624, much of the city’s native Peruvian sector was washed away as the San Salvador dam broke, killing around 200 and causing extensive destruction.

Licences to travel to the Andean Altiplano were tightly controlled, but many Spaniards sought work aboard merchant vessels – then abandoned their posts at the earliest opportunity. A trader of the period commented: “In every port where [merchant vessels] put down anchor, they jump ship and leave behind their duties and occupations, absenting themselves in anticipation of the liberties and uncertain riches of Potosí and other mining centres.” One resident of the city noted: “It seemed the land was swelling with rootless people who came each year from below and Spain to this villa, the stopping point for all the poor.”

Facebook Twitter Pinterest The discovery of silver turned this isolated Incan hamlet into the fourth largest city in the Christian world in just 70 years. Illustration: Rex/Shutterstock

The new arrivals began to clash with the Basque ruling class who had come to dominate the city , causing vicious gang wars. Thousands died in the fighting, fuelled by gossip and rumours that travelled on the icy Andean wind.



By the early 1620s, the El Dorado myth was beginning to fall apart – exacerbated by the decaying infrastructure, falling yields and social tensions.“The metals are not reborn, nor do they grow anew,” as one writer had it. “For about 70 years now, a great quantity of ore has been mined … It is no great surprise that the good ores have been exhausted, and that all have diminished.”

Everything is finished, all is affliction and anguish … This has been one of the greatest downfalls ever

From its boom-town peak at 160,000, the city’s population had fallen to 60,000 by the end of the 17th century. “Everything is finished,” wrote another resident. “All is affliction and anguish, weeping and sighing. Without doubt this has been one of the greatest downfalls ever.”

The pieces of eight from Potosí that had poured into China’s Ming dynasty eventually proved inflationary, making the city’s mining operations less profitable and lowering the price of silver around the world.

But the city’s silver had changed the world forever, facilitating the exchange of slaves, fabrics, spices and other goods across the globe. Much discussed in The Wealth of Nations by Adam Smith, it had helped fund the Spanish empire’s wars with the British, Dutch, and French – and helped them overcome the Ottomans. American silver prompted King Philip IV of Spain to proclaim: “In silver lies the security and strength of my monarchy.” But this assumption of unlimited wealth from the Americas proved ruinous, fuelling an unsustainable level of spending by the Spanish royals.



Potosí survived as a mining centre on a smaller scale until its liberation by Simón Bolívar in 1825, its former riches now existing only in legend and literature. “To be worth a Potosí” appears in Don Quijote de la Mancha, a phrase that is still used in Spanish to this day.

Facebook Twitter Pinterest The city of Potosí today is a shell of its former self. Photograph: Aizar Raldes/AFP/Getty Images

The city is also an important symbol in modern Latin American revolutionary movements, made famous by Eduardo Galeano’s book Open Veins of Latin America – which was a gift from Venezuela’s president Hugo Chávez to Barack Obama in 2009.

Galeano’s furious account of Potosí’s past remains the most popular version of the city’s history, writing of 8 million dead native Peruvians in the abandoned and flooded mines around the city. “You could build a silver bridge from Potosí to Madrid from what was mined here – and one back with the bones of those that died taking it out,” say many residents, quoting from Galeano’s book, although there is little evidence of a genocide of such proportions.

There are no reliable mortality statistics about the mining and associated processes, according to Dr Ignacio Gonzalez Casasnovas, an expert on the social history of Potosí, “but we would estimate the toll to be much less than the 8 million deaths of which Galeano spoke.”

Casasnovas is far more certain of the city’s impact on the world: “At a time when European powers were expanding, both economically and technologically, it facilitated the globalisation of the world’s economy. Potosí’s silver reached Seville, but also Rouen and Calais, Amsterdam and Macao.”

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Modern Potosí is a shell of its former self. The mountain still towers over the city but it is crumbling inside, made unstable by the hundreds of miles of mine shafts constructed over the 500 years it has been exploited. In 2011, the upper cone of the mountain collapsed.

It is now predominantly mined for zinc and tin, although children still look through the piles of ore for the silver that once made their city so wealthy. Many of the Bolivians who still work in the mines suffer from the same illnesses as those who died at the hands of the Spanish – their lungs turned black by the dust. “For many miners, their fathers also died of silicosis, and they entered the mine at an early age. There’s a culture of death here,” one miner told Al Jazeera in 2014.

The poverty and dilapidation of modern Potosí mask the story of a once-imperial city whose grand villas are now restaurants, hairdressers and dental surgeries. But high in the Andes above the treeline, the rich mountain remains – its contents now in Armada shipwrecks, the jewellery of Arab rulers, and the remaining treasures of the Ming dynasty. Few places in the world were left untouched by its riches.

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