National Geographic explorers test their mettle against lava, ice, rock and wind. Check out some epic moments from recent expeditions. (Full story: http://on.natgeo.com/1LRfzy2)
  1. Inside the Volcano
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    A team of scientists journeyed into the caldera of the Nyiragongo volcano located in the Democratic Republic of Congo (pictured here). "Down here you feel the volcano," says photographer Carsten Peter. "It's a low-frequency rumbling that pulses through your body—like being inside a giant subwoofer." (Photo by Carsten Peter, National Geographic Creative)
  2. Clinging to a Lifeline
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    Climber-photographer Cory Richards traverses an exposed ridgeline during an attempt to summit Myanmar’s Hkakabo Razi, said to be Southeast Asia’s highest peak. Just to reach the remote, little-known mountain required a two-week trek through dense jungle. (Photograph by Renan Ozturk, National Geographic Creative)
  3. Empire of Rock
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    Climber Emily Harrington scales the face of southern China’s Moon Hill—an arch formed from the remains of a collapsed cave, called a karst. Sightseers have the less arduous option of walking a dirt path to the top. (Photo by Carsten Peter, National Geographic Creative)
  4. The Forever Volcano
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    Photographer Carsten Peter takes a moment to pose for a self-portrait in front of an erupting Mount Semeru on the Indonesian island of Java. Semeru has been in a state of near-constant eruption since 1967. (Photo by Carsten Peter, National Geographic Creative)
  5. One Woman, 14 Killer Peaks
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    Battling wind-whipped snow on Pakistan’s K2, the world’s second tallest mountain, Gerlinde Kaltenbrunner checks the ropes her team has spent weeks fixing along the route—9,000 feet in all. On this expedition, she became the first woman to climb all 14 of the world’s 8,000-meter peaks without oxygen. (Photo by Ralf Dujmovits, National Geographic)
  6. Journey Across the Top of the World
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    A male polar bear stares at the tent of two adventurers who set out to cross Russia's remote Franz Josef Land—the world's northernmost archipelago—in a bid to retrace the steps that Fridtjof Nansen, Norway's pioneering polar explorer, had taken 112 years before. (Photo by Borge Ousland, National Geographic)
  7. The Breaking Point
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    Veteran climbers Cory Richards and Mark Jenkins were forced to abandon their quest to summit Hkakabo Razi when faced with certain death. “We wanted an old-school adventure, and we got one,” says Jenkins. As for success? “The mountain always decides.” (Photo by Renan Ozturk, National Geographic)
  8. South Pole Ascent
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    Adventurer Mike Libecki hauls himself up an unclimbed tower in the Wohlthat Mountains of Antarctica’s Queen Maud Land. The team struggled against frequent katabatic winds—powerful, avalanche-like sheets of cold air that hurtle down mountain corridors—that destroyed their camp. (Photo by Cory Richards, National Geographic Creative)
  9. Rope-Free on Thank God Ledge
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    A new crop of super climbers is going ropeless. Alex Honnold, one of the world's most gifted free soloists, shattered speed records while climbing Yosemite's Half Dome. Here, he roosts on its Thank God Ledge. The 30 seconds it takes to traverse requires absolutely no technical climbing skill, but Honnold admits it’s sobering to look at 1,800 feet of air. (Photo by Jimmy Chin, National Geographic)
  10. A Tradition of Risk
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    Lakpa Sherpa pauses in a moment of reflection while guiding a group of climbers up 22,349-foot-tall Ama Dablam in the Himalaya. Nepal’s ethnic Sherpa community has been helping alpinists ascend nearby Everest, the world’s tallest mountain, since 1953. The devastating 2014 Everest avalanche that claimed the lives of 16 expedition workers threw into sharp focus the perils facing Sherpas and their traditional livelihood. (Photo by Aaron Huey, National Geographic Creative)
  11. High-Altitude Hazards
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    The light from headlamps illuminates a column of mountaineers climbing through early morning darkness toward the summit of Mount Everest. Climbing Earth's tallest peak requires overcoming numerous natural dangers—thin air, unpredictable weather, unstable ice falls—but increasingly alpinists face a number of human-driven hazards: bottlenecks of climbers along the routes, too many inexperienced mountaineers, and insufficient safety precautions. (Photo by Kristoffer Erickson, National Geographic)