Less than two miles from Iceland’s Reykjavik airport sits a nondescript metal building as monolithic and drab as a commercial poultry barn. There’s a deafening racket inside, too, but it doesn’t come from clucking chickens. Instead, tens of thousands of whirring GPUs perform the complex, exhaustive calculations needed to verify cryptocurrency transactions and add them to the public record, otherwise known as the blockchain. Hundreds of thousands of fans blast cold air to keep the machines from overheating, aided by six giant ceiling turbines that spin with the collective force of 360 washing machines.

The facility, called Enigma and established by Genesis Mining in 2014, is easily the loudest environment that British photographer Lisa Barnard has ever documented. She visited two years ago while shooting her project Bitcoin. “The biggest thing I remember was just the noise and the flashing lights and wiring,” Barnard says. “It was like being inside a computer.”

The high-tech barn seems worlds away from the geysers, waterfalls, and lagoons that inspire 2.3 million tourists each year (not to mention a few Björk lyrics), but it’s as much a product of Iceland’s unique geology as any of those. The Nordic island country straddles the Mid-Atlantic Ridge, where the Eurasian and North American tectonic plates meet, molding a volcanic terrain webbed by glacial rivers and studded with gemstone-aquamarine lakes. The abundant water and underground heat is harnessed by hydroelectric dams and geothermal power stations to produce cheap, green electricity that facilitates the energy-intensive process of confirming cryptocurrency transactions—called mining, since miners are rewarded for their efforts with newly minted and extremely volatile “coins.” The fact temperatures rarely top 57 degrees Fahrenheit also helps.

It wasn’t long after Bitcoin’s creation on January 3, 2009 that cryptocurrency companies began moving to Iceland. In 2016, large data centers accounted for nearly 1 percent of its GDP, with cryptocurrency mining operations making up 90 percent of those. They now use more electricity than all of Iceland’s homes combined, with electric bills at Enigma running more than $1 million per month. But however green the energy, miners still can’t escape a dilemma as old as picks and shovels: how to extract resources without marring the landscape. According to local experts cited by The Wall Street Journal, keeping up with demand for electricity requires building more dams and power stations that could alter Iceland’s unique, sensitive environment.

That tension intrigues Barnard. She became interested in cryptocurrencies while working on her new book The Canary and the Hammer, a visual exploration of gold. It piqued her interest in digital “gold” that isn’t controlled by a central bank, leading her from Bitcoin meet-ups in Japan, the first country to officially recognize cryptocurrencies, to data centers in Iceland, where they’re mined on an industrial scale. “I was interested in this idea of it being an equitable currency,” Barnard says, “and yet it has the potential to be very destructive as far as the land is concerned.”

So, after photographing Enigma, she also ventured out to Svartsengi geothermal power station (which supplies electricity to crypto-miners and water to the Insta-famous Blue Lagoon) and other sites of thermal activity. Standing before ethereal, bubbling pools, she felt an almost palpable connection to the inner workings of the earth, “both terrifying and beautiful at the same time,” she says. The sulphur-smelling waters steamed and hissed, many decibels below the crypto-digital roar to which they’re weirdly—and maybe inextricably—linked.