Located on the banks of the Uruguay River and named after a 17th-Century hermit, the sleepy town of Fray Bentos produced one of the most influential food brands of the 20th Century.

“The company claimed it used every part of the cow except for the moo,” said Diana Cerilla, guiding me into the heart of what she calls the ‘killing room’. In the 1930s, as many as 1,600 cows a day – plus thousands of sheep, pigs, chickens and other animals – met their end in this slaughterhouse, before being processed, packaged and exported around the world. I scanned the grisly array of hooks, pulleys, wheels, chains, conveyors and scales, immobile but ominous, and started to shiver.

On the surface, a long-abandoned meat processing plant on the edge of a sleepy town in the Uruguayan countryside does not sound like the most obvious tourist destination, let alone a Unesco World Heritage site. But the Paisaje Industrial Fray Bentos (Fray Bentos Industrial Landscape) had a profound impact on the way the world eats, creating one of the best-known British brands of the 20th Century, transforming the Uruguayan economy and helping to move global food production into the industrial age. Moreover, the site is an impressive display of once cutting-edge, now slowly rusting Edwardian- and Victorian-era technology. It even, in certain lights, has an eerie beauty, at least for someone with a passion for industrial archaeology.

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The complex dates to 1863 when the Liebig Extract of Meat Company founded a factory on the banks of the Uruguay River and started churning out ‘beef extract’ using a technique patented by pioneering German chemist Justus von Liebig. Cheap cuts of meat – widely available here, thanks to Uruguay’s burgeoning cattle ranches – were boiled down to produce a nutritious stock that was originally aimed at convalescing patients. The process was subsequently refined, the liquid solidified, and Oxo – small crumbly cubes of stock – came into being.

The company used every part of the cow except for the moo

A town grew up alongside the German-run, British-financed factory, as workers flocked here from across Uruguay and around 60 other countries. Originally called Villa Independencia, the town was later renamed after a 17th-Century Uruguayan hermit, called Fray Bentos (Friar Benedict in English), who reputedly lived in a nearby cave. Soon Liebig was producing another popular product from off-cuts of meat: tinned corned beef. Oxo and corned beef became staples for working-class people across Europe for whom meat had previously been a luxury item. They also provided inexpensive, long-lasting and easy-to-carry rations for British soldiers during the Boer War and British and German troops in World War One, as well as for polar explorers like Robert Falcon Scott and Ernest Shackleton.

In 1924, the company was bought by the British Vestey Group and renamed Frigorífico Anglo del Uruguay. Taking advantage of fast-developing refrigeration technology, ‘El Anglo’ started exporting frozen meat around the world, alongside Oxo, corned beef and more than 200 other products, from leather to soap, sausages to jams. In 1943 alone, 16 million tins of corned beef were shipped out from Fray Bentos, the vast majority used to power the Allied war effort. The products even earned a royal following: “I remember eating corned beef until it came out of my ears,” Prince Charles told reporters when he visited Uruguay in 1999.

Today the plant is open to the public. The office buildings have been renovated and now house a museum with exhibits from the plant’s heyday, including vintage typewriters, classic posters, rudimentary firefighting equipment and rickety delivery trucks. Another section has been taken over by a local university, keeping alive the plant’s technological traditions. But most of the rambling complex has been left as it was, and wandering through these vast, silent, low-lit buildings is a haunting experience.

The engine room looks like a scene from a steampunk comic, with rusted diesel-powered generators, huge turbines and steam compressors festooned with levers, valves and wheels connected by a multitude of winding pipes and chimneys. On the walls next door are marble-panelled units covered with the dials and switches that controlled the plant’s electricity production: in 1883, this became the first place in Uruguay to generate electricity. “The factory reminds me of the Charlie Chaplin film Modern Times,” said Cerilla, the museum manager, as she showed me round.

I remember eating corned beef until it came out of my ears

Outside, a soaring water tower looms over a crowd of interlinked brick, concrete, glass and corrugated iron buildings. Many are off-limits for safety reasons, including the monolithic cold store, which once held up to 18,000 tonnes of frozen meat. But it is possible to poke round the Casa Grande, the manager’s house, an opulent mansion with stained glass windows, two pianos, hardwood floors and a gong to signal the start of a meal.

“This was the industrial revolution in Uruguay,” said guide Nicolás Cremella. “Fray Bentos was really important to Uruguay – it was the country’s real capital, not Montevideo. It was the only industrial meat company, and provided jobs throughout the country.” But while the company may have provided employment locally, the profits headed overseas.

Fray Bentos products remained popular in post-war Europe, but slowly fell out of favour as food technology developed and eating habits changed. The Anglo plant passed on to the Uruguayan government in the late 1960s, and eventually closed in 1979.

“It was a company town, and it was terrible for people when it finally shut down,” said Cerilla, whose father and grandfather worked at the plant. “Lots of people left, and many emigrated.”

Despite the initial gloom, Fray Bentos town recovered. Today it has a flourishing paper pulp industry, and in 2015 it received a further boost when Unesco granted the Anglo plant World Heritage Site status. (The Fray Bentos brand, incidentally, is now owned in the UK by Baxters, which still uses it for a range of tinned pies, puddings and meatballs.)

In the late afternoon, I headed back into town via Barrio Anglo, a suburb of around 300 homes built for the company’s senior staff. The smell of mowed grass, tree blossoms and barbeque smoke hung in the air as I wandered past clusters of simple bungalows with corrugated iron roofs and luxuriant gardens. Nearby were the golf, tennis, football and rowing clubs that once formed the focal point of expat life.

This was the industrial revolution in Uruguay

An insight into this period is provided by S W Johnson, a British manager at the plant in the 1930s. “We had the ‘Anglo Social and Athletic Club’, with its hall for dances, a snooker/billiards room, bridge room, library which only carried English books and magazines… and a bar (the Uruguayan attendant also accepted bets on the then illegal quiniela or numbers game)… As we were not then blessed or cursed with television, and the radio [was] mainly used for listening to the BBC, which brought news from ‘home’, we led a very active life,” he wrote in an account featured in Andrew Graham-Yooll’s Uruguay: A Travel and Literary Companion.

By the time I reached the town centre, it was early evening and life was returning as locals rose from their afternoon siestas. A group of children played hide-and-seek in the main square, Plaza Constitución, ducking down in the cast-iron bandstand, donated by the company to the town in 1902 and a replica of one that once stood at the Crystal Palace in London. Parents gathered on benches to sip mate, the local caffeine-rich herbal tea, while monk parakeets cawed from their perches in the many palm, willow and palo borracho trees.

For dinner, it seemed fitting to sample the product that, above all others, put the town on the map. Uruguayans eat more beef than anyone else in the world – around 56kg per person a year – and the cattle industry is a key part of the economy. But though Fray Bentos remains synonymous with corned beef, few locals eat it today. “We don’t like eating meat from tins, we like fresh meat,” Cremella told me. “People in Fray Bentos may have tins of corned beef at home, perhaps on the shelf as a [trinket or] souvenir, but not to eat.”

Sure enough, none of the restaurants I visited had corned beef on the menu, nor did the first three supermarkets I stopped in. Eventually, as I was on the verge of giving up, I found a small store with a couple of tins for sale: ‘Marca Uruguay – Industria Brazil’, the labels read: ‘Uruguay Brand – Made in Brazil’.

Places That Changed the World is a BBC Travel series looking into how a destination has made a significant impact on the entire planet.

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