National Geographic

Buffeted by stinging blasts of wind-driven snow, Gerlinde Kaltenbrunner checks the ropes the team has spent weeks fixing along the entire route—9,000 feet of rope in all. From the October 125th anniversary issue of National Geographic magazine © Ralf Dujmovits/National Geographic

A lion pushes through a dust storm in Kalahari Gemsbok National Park, South Africa. The weather had worsened to the point that it didn’t notice the photographer's approach. "I shot three rolls of him and just one picture turned out—serendipity," says Johns. From the October 125th anniversary issue of National Geographic magazine © Chris Johns/National Geographic

Snared and doomed by a gill net, a thresher shark is among an estimated 40 million sharks killed each year just for their fins. Drawing attention to this unsustainable practice has led some countries to ban the trade of shark fins, considered a delicacy in Asia. From the October 125th anniversary issue of National Geographic magazine © Brian Skerry/National Geographic

Under the black clouds of burning oil fields during the Gulf War, camels forage desperately for shrubs and water in southern Kuwait. Front-line photographs of regions ravaged by human strife can also illuminate war’s environmental cost. From the October 125th anniversary issue of National Geographic magazine © Steve McCurry/National Geographic

Its image mirrored in icy water, a polar bear travels submerged—a tactic often used to surprise prey. Scientists fear global warming could drive bears to extinction sometime this century. From the October 125th anniversary issue of National Geographic magazine © Paul Nicklen/National Geographic

A female elephant charges toward the photographer near Dzanga Bai. From the October 125th anniversary issue of National Geographic magazine © Michael Nichols/National Geographic

Destined to melt, an 800-pound chunk of ice glowed in the moonlight. It washed up in a lagoon created by a receding glacier, part of a worldwide shrinkage of glacial ice. From the October 125th anniversary issue of National Geographic magazine © James Balog/National Geographic

A single frame can transport us to one of our planet’s far-flung and beautiful places. In this one, stalactites and a sunbeam spotlight a swimmer in the Xkeken cenote, a natural well in the Yucatán thought by the Maya to lead to the underworld. From the October 125th anniversary issue of National Geographic magazine © John Stanmeyer/National Geographic

A lion climbs a tree to sleep, in Uganda’s Queen Elizabeth Park. From the October 125th anniversary issue of National Geographic magazine © Joel Sartore/National Geographic

An eight-pound rhino horn like this one can reap up to $360,000 on the black market. From the October 125th anniversary issue of National Geographic magazine © Brent Stirton/National Geographic

Noor Nisa, about 18, was pregnant and her water had just broken. Her husband was determined to get her to the hospital, but his car broke down. The photographer ended up taking Noor Nisa, her mother and her husband to the hospital, where she gave birth to a baby girl. From the October 125th anniversary issue of National Geographic magazine © Lynsey Addario/National Geographic

On Skye's Trotternish Peninsula, basalt pinnacles loom over the Sound of Raasay. Rising from the debris of an ancient landslide, they bear witness to the geologic upheavals that shaped these lands. From the October 125th anniversary issue of National Geographic magazine © Jim Richardson/National Geographic

An elevated view of about half of Machu Picchu, the lost mountaintop city of the Inca in the Peruvian Andes. National Geographic supported Bingham's excavations at the site from 1912 to 1915. From the October 125th anniversary issue of National Geographic magazine © Hiram Bingham/National Geographic

Photography pioneer Shiras made the first nighttime wildlife photos. Here he demonstrates his revolving camera tray, mounted jacklight, and handheld flashgun. From the October 125th anniversary issue of National Geographic magazine © George Shiras/National Geographic