Greenland ice cap

Fridtjof Nansen successfully crossed Greenland, demonstrating it was covered by a significant ice cap. That one ice cap is now known to contain ~8% of all the ice in the world.
 Fridtjof Nansen Norway 1888 Greenland ice cap

In 1888 the Norwegian explorer Fridtjof Nansen (1861-1930) landed on the eastern shore of Greenland with five others. All six managed to cross to the inhabited western shore in a six-week trek. It was the first time Greenland had ever been crossed. The crossing seemed to indicate that the entire interior of Greenland was buried under a huge ice cap, a last remnant of the Ice Age. That one ice cap is now known to contain about 8 percent of all the ice in the world.