Courtesy Eric Larsen
On May 7, 2014, after eight hours of hiking and swimming - while wearing insulated dry suits - polar explorers Eric Larsen and Ryan Waters reached the North Pole.
They'd traveled 3.5 nautical miles that day, the last leg of an almost 500 mile journey that took 53 days from start to finish.
As Larsen recently explained to Business Insider and describes in his book, "On Thin Ice: An Epic Final Quest into the Melting Arctic," written with Hudson Lindenberger, many expect their trek to be the last unsupported, unaided expedition across the frozen Arctic to the North Pole.
Here's what that journey looked like.