Ruzo has since published a book that reveals h ow fault-fed hot springs cause the river to boil

Academic experts told him that it couldn't exist because the Amazon basin is far from volcanic activity

The river in Mayantuyacu was found by Andrés Ruzo after his


A mysterious, four-mile long river, deep in the heart of the Amazon, is so hot that it boils.

The river has long been a legend in Peru, but when geoscientist Andrés Ruzo's heard about it, he thought such a phenomenon couldn't possibly exist.

He believed that it would require a huge amount of geothermal heat to boil even a small river, and the Amazon basin is far from any active volcanoes.

But then, Ruzo saw the legendary boiling river with his own eyes.

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A four-mile long river, deep in the heart of the Amazon, is so hot that it boils. The river has long been a legend in Peru, but when geoscientist Andrés Ruzo (pictured) heard about it, he thought such a phenomenon was impossible. But then, he saw it with his own eyes

WHY DOES THE RIVER BOIL? Part of the river in Mayantuyacu boils because of fault-fed hot springs. When rain falls on the surrounding area, it gathers into the porous sedimentary rock. As it move through the rock, it heats up from the primal heat of the Earth. Eventually, it comes across a large thrust fault, or crack. As water falls behind it, it forces the now heated water to ascend along the fault-line to surface as a hot or warm spring. Advertisement

Ruzo first heard about the Mayantuyacu river when his grandfather told him a story about how Spanish conquistadors killed the last Inca emperor.

He said that after the murder, the Spanish conquistadors headed into the Amazon rainforest in search of gold.

When they returned, the men spoke of a terrifying experience that involved poisoned water, man-eating snakes and a river that boils from below.

Twelve years later, at a family dinner, Ruzo heard the river mentioned again when his aunt said that she had visited it.

The river fascinated him growing up. As a PhD student in geophysics at Southern Methodist University in Texas, Ruzo wanted to find the river for himself.

'I began asking that question. Could the boiling river exist?, Ruzo said in Ted Talk.

'I asked colleagues from universities, the government, oil, gas and mining companies, and the answer was a unanimous no.

'And this makes sense. You see, boiling rivers do exist in the world, but they're generally associated with volcanoes. You need a powerful heat source to produce such a large geothermal manifestation.

Ruzo heard about the river when his grandfather told him a story about how Spanish conquistadors killed the last Inca emperor. The story goes that after the murder, the Spanish conquistador headed into the Amazon rainforest in search of gold. When they returned, the men spoke of a terrifying experience that involved a river that boils from below. Pictured on the right is a shaman that guards the river

As a PhD student in geophysics at Southern Methodist University, Ruzo wanted to find the river for himself. 'I began asking that question. Could the boiling river exist?, Ruzo said in Ted Talk. 'I asked colleagues from universities, the government, oil, gas and mining companies, and the answer was a unanimous no'

This frog did not survive its encounter with the river. 'I've seen all sorts of animals fall in, and what's shocking to me, is the process is pretty much the same,' said Runzo. 'So they fall in and the first thing to go are the eyes. Eyes, apparently, cook very quickly'

Dipping my hand into the river would give me third-degree burns in less than half a second

'Telling this same story at a family dinner, my aunt tells me, "But no, Andrés, I've been there. I've swum in that river".'

Despite his skepticism, Runzo found himslef hiking into the jungle in 2011, guided by his aunt, far from the he nearest volcanic center.

He said he was mentally preparing to behold the legendary 'warm stream of the Amazon' - but what he saw was very different.

Runzo discovered a four mile 'boiling river' in the sacred geothermal healing site of the Asháninka people in Mayantuyacu.

At its widest, it is 82ft (25 metres), and around 20ft (six metres) deep. The water is hot enough to brew tea, according to a report in Gizmodo, and in some parts, it boils over.

'Dipping my hand into the river would give me third-degree burns in less than half a second,' Ruzo told Ted.com 'Falling in could easily kill me.'

The river boils because of fault-fed hot springs.

'As we have hot blood running through our veins and arteries, so, too, the Earth has hot water running through its cracks and faults,' Runzo explained in a Ted speech.

'Telling this same story at a family dinner, my aunt tells me, 'But no, Andrés, I've been there. I've swum in that river.' Despite his skepticism, Runzo found myself hiking into the jungle, guided by his aunt, far from the he nearest volcanic center

Runzo discovered a four mile 'boiling river' in the sacred geothermal healing site of the Asháninka people in Mayantuyacu. At its widest, it is 82ft (25 metres), and around 20ft (six metres) deep. The water is hot enough to brew tea, according to a report in Gizmodo , and in some parts, it boils over.

'Where these arteries come to the surface, these earth arteries, we'll get geothermal manifestations: fumaroles, hot springs and in our case, the boiling river.

Parts of the river are so hot that any animals that falls in boils instantly.

'I've seen all sorts of animals fall in, and what's shocking to me, is the process is pretty much the same,' said Runzo.

'So they fall in and the first thing to go are the eyes. Eyes, apparently, cook very quickly. They turn this milky-white color. The stream is carrying them.

'They're trying to swim out, but their meat is cooking on the bone because it's so hot. So they're losing power, losing power, until finally they get to a point where hot water goes into their mouths and they cook from the inside out.'

For some reason, the river has escaped scientific scrutiny. But Ruzo is on a mission to change that.

He has published a book, 'The Boiling River: Adventure and Discovery in the Amazon,' that publicises the river for the first time.

Ruzo's is now trying to save the boiling river. The surrounding forest has been destroyed by logging practices, and if action isn't taken, the area could vanish entirely.

'In the middle of my PhD, I realized, this river is a natural wonder,' Ruzo told Gizmodo. 'And it's not going to be around unless we do something about it.'

Extracted from The Boiling River by Andrés Ruzo published by Simon & Schuster £7.99. Copyright © 2016 by Andrés Ruzo

Ruzo's is now trying to save the boiling river. The surrounding forest has been destroyed by logging practices, and if action isn't taken, the area could vanish entirely