The Mountain That Ate Men
In 1545 someone found silver in a hill at 4,090 metres, and the coin struck from it became the first global currency — circulating from Seville to Ming China. The bill was paid by the men sent underground under the mita, and the mountain is still being worked today by cooperatives with hand drills.
The Cerro Rico stands over Potosí like a spoil heap the size of a mountain, which is roughly what it has become. Red-brown, conical, stripped of vegetation and perforated by something in the order of tens of thousands of tunnel entrances accumulated over five centuries, it is visible from every street in the city and from a long way out across the altiplano. At 4,090 metres, Potosí is among the highest cities of its size on earth, and it exists for one reason: in 1545 someone found silver in that hill, and it turned out to be the largest deposit anyone had ever found anywhere.
What followed is not a footnote in economic history. It is arguably the origin of the modern global economy — and it was paid for, in a currency the ledgers do not record, by the people who went into the tunnels.
The richest city in the world
Within a few decades of the strike, Potosí had grown from nothing to one of the largest cities in the world, comparable in population to London or Paris at the time and situated in thin air two thousand kilometres from the nearest ocean. The Spanish crown built a royal mint here, the Casa de la Moneda, whose surviving building is now the best museum in Bolivia and whose wooden gear trains — driven by mules in the basement — rolled silver into sheets for coining.
The coin they struck, the piece of eight, became the first genuinely global currency. It circulated in Europe, in the Ottoman lands, in India, and above all in China, where demand for silver to pay taxes under the Ming absorbed an enormous share of American output. The galleons that ran from Acapulco to Manila carried Potosí silver west across the Pacific; the Atlantic fleets carried it east. A mountain in the Andes was, for well over a century, the monetary base of world trade.
The Spanish phrase vale un Potosí — it is worth a Potosí — entered the language as a superlative for wealth and remains in Spanish dictionaries. The city’s coat of arms, granted by Charles V, carries a legend describing it as the treasure of the world and the envy of kings.
The mita
The labour system that made this possible was called the mita. The Spanish adapted the name and the outline from an Inca institution of rotational public service and turned it into something categorically different.
Indigenous communities across a vast catchment of the southern Andes were required to send a fixed proportion of their adult men to Potosí on rotation. They walked for weeks to get there, worked underground for a term, and — if they survived — walked home. The wage did not cover subsistence. Many communities responded by abandoning their villages entirely to escape the draft, which depopulated whole provinces and is visible in colonial census records as a demographic collapse.
Underground, the conditions were what one would expect of hand-cut tunnels at 4,000 metres with no ventilation. Rockfall, silicosis from dust, and mercury poisoning from the amalgamation process used to separate silver from ore — a technique that consumed enormous quantities of mercury shipped in from Huancavelica in Peru, itself worked by the same system.
When Indigenous labour ran short, enslaved Africans were shipped in, many of whom died quickly at an altitude their bodies had no preparation for. The survivors and their descendants form the Afro-Bolivian community of the Yungas today.
Estimates of the total death toll across three centuries vary enormously — the figures cited range from the hundreds of thousands into the millions, and no serious historian claims precision. What is not in dispute is the scale, or the phrase Bolivians use for the hill: el cerro que come hombres. The mountain that eats men.
Europe got the coinage of a world economy. The altiplano got a hole in a mountain and a demographic hole beside it.
What is left in the tunnels
The silver is essentially gone. What remains is low-grade ore — tin, zinc, lead, with silver as a by-product — worked today not by a company but by cooperatives: associations of miners who hold concessions, own their own tools, sell to processors at fluctuating world prices, and operate with a degree of formal safety regulation that is, in practice, minimal.
The work is done much as it was: hand drills and pneumatic drills where there is compressed air, dynamite bought at the miners’ market in town by anyone who wants it, ore hauled out in wagons pushed by hand. Ventilation is whatever the tunnel geometry provides. Silicosis remains the characteristic disease and continues to shorten lives in a way that is documented and locally understood as normal.
Underground, in most working shafts, there is a figure called El Tío — the Uncle — a horned clay statue with a lit cigarette in its mouth and offerings of coca leaf and neat alcohol at its feet. The miners’ theology is precise about this: God rules above ground, and below ground the mountain belongs to someone else, who must be kept satisfied. Tuesdays and Fridays are the days for offerings. It is not folklore performed for visitors; the statues are maintained by the men who work the shaft.
Structurally, the Cerro Rico is in trouble. Five centuries of tunnelling have left the summit honeycombed, subsidence has been measured, and there have been repeated official attempts to close the upper levels and stabilise the peak, generally resisted by cooperatives whose livelihoods are inside them. UNESCO, which inscribed Potosí as a World Heritage site in 1987, added it to the danger list in 2014 over exactly this.
The silver that never stayed
One of the more useful things Potosí teaches is that extraordinary resource wealth and lasting prosperity are unrelated variables.
Very little of the silver remained in the Andes. It went by mule train to the Pacific at Arica, north to Lima, and out with the treasure fleets — or east across the continent to the Río de la Plata, which is how Buenos Aires acquired both its name and its early significance. In Spain it funded the Habsburg wars, and much of it passed straight through to Genoese and Dutch creditors and to Asian markets that wanted silver and had goods Europe wanted.
Economic historians have argued for a century about what this did to Spain itself. The broad shape of the argument is that a sustained inflow of bullion pushed up domestic prices, made Spanish manufacture uncompetitive against imports, and removed the fiscal pressure that in other states forced the construction of a productive tax base. It is one of the founding cases in the literature on the resource curse, and it was observed at the time — Spanish writers of the seventeenth century wrote about their country being a bridge that carried silver from one side to the other while remaining poor.
Bolivia has run the same experiment repeatedly since. Silver, then tin — the Patiño fortune, one of the largest in the world in its day, built on Bolivian tin and held almost entirely abroad. Then natural gas. Now lithium, in the brines under the Salar de Uyuni, in one of the largest resource concentrations on earth, with the state attempting to structure the industry so that the processing and the value stay in the country rather than leaving as raw brine.
Whether that works is the open question of Bolivian economic policy. The historical base rate is not encouraging, which every Bolivian who has stood in front of the Cerro Rico already knows.
The question of the mine tour
Potosí is one of the few places in the world where tourists can enter a working mine, and the ethics of doing so deserve more thought than they usually get.
The case for: the tours are guided almost entirely by former miners, the income is substantially better and considerably safer than the alternative, visitors buy coca, drinks and dynamite as gifts for the working crews, and the practice keeps international attention on conditions that would otherwise be invisible. Miners themselves generally support it.
The case against: it is dangerous, in a real rather than theatrical sense — the tunnels are low, hot, dusty, unlit, and occasionally have live blasting elsewhere in the system. Silica dust does not distinguish between a miner and a visitor, although two hours is not thirty years. And there is a genuine question about whether watching people do lethal work for a wage constitutes witness or spectacle.
If you go, the practical rules are: choose an operator run by ex-miners with a stated safety protocol, do not go if you are claustrophobic or unacclimatised, take the gifts, take photographs only when invited, and do not treat El Tío as a photo opportunity. If you do not go, the Casa de la Moneda tells most of the same story without any of the ambiguity.
The city above
What almost nobody expects is that Potosí is beautiful. The colonial wealth built a city of churches out of proportion to any place its size — San Lorenzo de Carangas with its carved mestizo-baroque portal, the Compañía de Jesús with its bell tower like a stage set, and dozens more in various states of restoration.
The streets are narrow, steep and cold. The altitude makes a flight of stairs an event. Wander into the market and the food is unapologetically highland: soups thick with wheat and potato, llama meat, and salteñas eaten mid-morning by everyone.
It is also, straightforwardly, a poor city in one of South America’s poorer countries, and there is no version of the visit that resolves that against the coat of arms on the wall of the mint. The two facts sit next to each other for as long as you stay, which is the reason to come.
Kwame edits ExplWorld’s Africa coverage and drives the continent’s worst roads personally to keep the guides honest. Formerly of the BBC’s Lagos bureau, he has crossed the Sahel five times and maintains the magazine’s overland-border database himself.