Spectacular but woefully underappreciated natural wonders are tucked away all over the planet. Granted, visiting some of them might leave you sweaty, faint, and gasping for breath.
Hardly anyone goes to see Turkmenistan’s Door to Hell, for instance, even though it offers the rare chance to see a giant fire-filled pit in the middle of a barren desert. The origins of the crater are a bit mysterious, but the most-told version has Soviet geologists igniting a natural gas seep in 1971 after an oil rig collapsed into the ground. The pit has been burning ever since.
During a 2013 expedition funded in part by the National Geographic Society, George Kourounis became the first—and, so far, only—person to don a silvery flame-resistant suit and lower himself into the inferno like a baked potato.
“When it comes to hellish places that want to kill you, I’m kind of an expert,” says Kourounis, an explorer and storm chaser who puts the Door to Hell on the top of his personal awful-places list.
“The very first time I walked up to the edge and felt the heat, my first reaction was, I don’t know if I’m going to be able to do this,” he says. “I’ve been inside a lot of volcanoes, and I’ve been around a lot of lava. And this was very intimidating.”
Did I mention there’s no fence around the Door to Hell? If you’re feeling lucky, you can just walk right up to the edge and sense the soil crumbling under your feet.
For those feeling less adventurous, let’s take a virtual world tour of the most gloriously awful destinations, no gas masks or special suits required.
The Door to Hell isn’t the only place that’s been compared to the underworld. The Phlegrean Fields in southern Italy offer visitors a glimpse of a sulphurous inferno right on the planet’s surface.
Sitting west of Naples, the fields are in a caldera, the cauldron-like depression that forms after a volcano has ejected huge amounts of magma. The site has erupted many times over thousands of years and continues to form fumaroles, gashes in the ground that emit steam and gases.
“The ground moves, the earth shakes, and scalding, stinking steam rises from hissing fissures,” as Atlas Obscura described the hellscape.
The site is popular with tourists who are supposed to view it from behind fences, but it still proves deadly on occasion. In September, three members of an Italian family died when an 11-year-old boy climbed the fence and his parents tried to rescue him from a fumarole.
Sulphur combusts on contact with air to create stunning blue lava-like rivers of light in the Kawah Ijen crater on the island of Java.
PHOTOGRAPH BY SONNY TUMBELAKA, AFP, GETTY IMAGES
For more surreptitious deadliness, few places top Indonesia’s Kawah Ijen volcano. A stunningly turquoise lake sits at its peak, and at night, electric-blue flames roll down the mountainside. It’s gorgeous—but the lake is full of hydrochloric acid, and the roiling blue is fuelled by choking sulphurous fumes.
The lake’s water is more corrosive than battery acid, a product of hydrogen chloride gas spewing from the volcano, which also hisses out sulphur-containing gases that burn bright blue on contact with air. Some of the gas condenses into liquid sulphur that cascades downhill as it burns.
“I’ve taken an inflatable rubber raft out onto this lake of acid, and it’s a surreal place,” Kourounis says. It’s also an active sulphur mine, and Kourounis has watched miners working there. “The only protection they have from the sulphur dioxide gas is a wet rag stuffed in their mouth, and they breathe through that all day long, and it dissolves away their front teeth,” he says. “It’s awful.”
Another colourful-yet-inhospitable place is Tanzania’s Lake Natron. The lake is bright red thanks to cyanobacteria living in its salty waters, which are almost as basic as ammonia and can reach temperatures of 49°C.
While Lake Natron isn’t a great place to take a dip, its shores are an important habitat for flamingos, which get their pink colour from eating the red cyanobacteria.
Earth’s lowest volcano on land sits below sea level at Dallol, Ethiopia. Among the crusty salt formations in its craters, hot acid pools mingle with crusts of sulfur-bearing minerals and deadly gases.
PHOTOGRAPH BY CARSEN PETER, NATIONAL GEOGRAPHIC CREATIVE
Set against the bright white of an Antarctic glacier, it’s hard to miss a blood-red waterfall five stories high.
Blood Falls was discovered in 1911, and scientists thought the water’s red colour might come from algae. But in June, University of Alaska scientists released new maps showing how iron-laden saltwater makes its way through cracks and fissures in the ice. When the water reaches the air, the iron reacts with oxygen and turns red, like rust.
Still, the bloody-looking water is filled with life. The waters that feed Blood Falls are highly unusual, scientists discovered, because they are ancient liquids that come only from the glacier itself, not rain or snow. Microbes living there are adapted to the below-freezing temperatures, extreme saltiness, and higher pressure found in the guts of this massive glacier.
Then there’s the Dry Falls of Coulee City, Washington. This is a place that won’t kill you, frighten the kids, or make anyone squeamish. It’s just a bit sad.
Dry Falls is the greatest waterfall that ever existed, except that you can’t see it. During the last ice age, the falls were 10 times larger than Niagara Falls is today, with water dropping 120 metres over a five-kilometre-wide span.
Today, it’s a lake with some nice tall cliffs—a far cry from its former glory. The best the Oregonian newspaper could muster about the former falls is that it’s “well worth a pit stop.”
Mexico’s Naica Crystal Cave is home to the biggest crystals in the world, but there’s a reason it’s not full of gawking tourists. Magma lurks just below the cave, and the few people who’ve ventured inside risked heat stroke.
“The air temperature is like 50 degrees Celsius with almost a hundred percent humidity,” Kourounis says. “As soon as you walk in, you start to die.”
It took Kourounis two years to get permission to spend one day in the cavern, but once there he wasn’t disappointed. “It looks like Superman’s Fortress of Solitude,” he says. The rest of us will probably never have the chance to see its terrible beauty—after mining operations ceased at the site in 2015, it re-flooded with groundwater.
Namibia's Dead Valley, or Deadvlei, has a stark beauty filled with dead acacia trees and some of the world's largest sand dunes.
PHOTOGRAPH BY TON KOENE, VW PICS, AP
You can, however, visit a lake that’s been called “the most electric place on Earth.” Lightning crackles more than 200 days a year over the spot where Venezuela’s Catatumbo River meets Lake Maracaibo, with as many as 280 strikes an hour.
The lightning here is so intense that it has its own name, the Catatumbo Lightning, and scientists have measured strikes and atmospheric conditions there to figure out why this particular location is such a hot spot. Some scientists think that ionised methane accumulating in the atmosphere at night makes the electric field stronger over the site.
But the lightning may have a more mundane explanation: Warm winds off the Caribbean are trapped in the lake basin, where they meet cooler air coming off the Andes Mountains. Those are pretty normal ingredients for building thunderclouds, and the conditions just happen to be unusually consistent in this particular spot.
DON’T TOUCH THE RAINBOW
The blue water at the centre of Yellowstone National Park’s most famous hot springs could give you a third-degree burn in under a second. But it sure is pretty.
The Grand Prismatic Spring, often called simply the rainbow hot spring, really is rainbow-coloured. The water in the centre of the spring is the hottest, reaching 87°C, so not much can live in it. That leaves it transparent and—because water scatters blue light—a beautiful cerulean hue.
As the water moves from the centre of the spring and cools, cyanobacteria that can tolerate its heat level take over. Synechococcus produce yellow pigments in harsh conditions, making up the next-hottest band, followed by a more diverse mix of life in the cooler outer rings.
As with many of these amazing places, the hot spring actually faces more risk from people than people do from it. In 2014, tourists crashed a drone into the centre of the steamy pool, and in 2016, Canadian tourists were filmed trampling the delicate site.
So, for everyone’s sake—look, but don’t touch.
Lead Image: The Door to Hell is a crater in a large natural gas field that has been burning for decades. PHOTOGRAPH BY GEORGE KOUROUNIS, NATIONAL GEOGRAPHIC CREATIVE