Aleksandr Kolchak is best known as the man who led the White Russian government that opposed the Communists in the revolution and who was executed by the Bolsheviks in 1920. But explorers and geography nerds remember Kolchak as the young Russian Navy officer who, just 11 years earlier, calculated the whereabouts of the most remote place in all of the vast Arctic—a spot some 400 miles from the geographic North Pole that he said was “permanently covered with the ice fields of the Arctic Pack and inaccessible to navigation.” Because nothing is more alluring than a place that supposedly can’t be reached, the “pole of inaccessibility” would become an irresistible challenge for generations of adventurers. And it still is.

Numerous expeditions have tried to cross the churning sea ice to reach the theoretical pole—the location in the Arctic Ocean farthest from any land. They failed in part because the exact location has shifted over the years with the discovery of previously undetected islands. In 2013, researchers using high-resolution satellite imagery and mapping software placed the pole of inaccessibility at 86 degrees north latitude and 176 degrees east longitude, or about 125 miles from Kolchak’s original. Gareth Rees, a physicist with the Scott Polar Research Institute at the University of Cambridge, who collaborated on the new finding, is confident they have it right—for now. Climate change and rising sea levels may eventually reshape coastlines, and thus move the pole.

The veteran Arctic explorer Jim McNeill, of England, has launched two expeditions to prove that the pole is accessible after all, but he was thwarted by illness in 2003 and disintegrating ice in 2006. This February, in the most ambitious attempt yet, McNeill and 28 volunteers will set out again, from northern Canada; they’ll travel on cross-country skis and pull sledges that double as kayaks in case they encounter open water. As the world gets smaller, the pole of inaccessibility beckons as one of the few remaining firsts in exploration, McNeill says: “I’m amazed that there could still be a place no one has ever reached.”