Sebastian Copeland and Mark George's Record 404-Mile Trek Across Australia’s Simpson Desert

Mark and Sebastian face growing dune elevations and long mud-flats nearing the end of their journey. Credit: Photographs by Ryan Claypool

On August 29, Sebastian Copeland and Mark George completed a 404-mile self-supported trek across Australia’s Simpson Desert by foot, the longest such crossing ever attempted in the latitudinal axis — by far the Simpson's toughest direction, given close to 1,000 dunes to cross. The feat took the two men a record-setting 26 days. The Simpson is known as the dead heart of Australia, and considered one of the harshest environments on the planet.

Over the course of the hike, Copeland and George trudged up and down more than 900 sand dunes, each man towing a 400-pound cart of food, water, solar panels, camping gear, and other supplies, behind him. Water made up the majority of each cart’s weight. “We calculated five liters of water per person, per day,” says Copeland. “So we each started with 135 liters [35 gallons] of water, which is about 300 pounds.”

Thankfully, the weight of the carts continually decreased as the men consumed food and water, but the temperatures were at their hottest — about 95 degrees — at the start of the trip, when the carts were the heaviest. Copeland, the larger of the two men at six feet four inches, 215 pounds, immediately struggled with thirst. “When you subtract water with breakfast, and more with dinner, you’re left with 3.5 liters for 8–11 hours of trekking, and it just wasn’t enough for me,” he says. “I had no saliva left in my mouth. It felt like I’d swallowed an ashtray.”

To combat the heat, Copeland and George started each day before dawn and rested during the hottest part of the day — 1:00 p.m. to 4:00 p.m. — by laying underneath the carts for shade. Copeland figured he could drink 300 milliliters (about three mouthfuls) of water an hour while moving. “I’d swish each mouthful for two to three minutes before I drank it to try and relieve the dryness,” says Copeland. “It was never enough."

The situation didn’t improve for Copeland, even as the carts became lighter and the daytime temperatures more bearable. He became too dehydrated to digest the nuts he’d brought, one of his high-calorie staples for long expeditions, and ended up losing 20 pounds in 26 days.

Despite the agony, Copeland says the expedition was worth it. He and George were using it as a test run for an even more difficult expedition in 2017 — a 480-mile self-supported journey across the fractured ice of the Arctic Sea to the North Pole. “It’s one thing to be a good athlete and to be generally compatible,” says Copeland, “but being able to test each other’s mental game, and our ability to push and pull each other, provides a whole other level of confidence. That’s exactly what we were able to accomplish in the Simpson.”

And the trip wasn’t a complete sufferfest. Copeland says the night sky, vast and silent, home to hundreds of thousands of stars, every one visible, was worth the price of admission. Plus, they got to see the world’s deadliest snake, the Inland Taipan, which delivers enough venom in one bite to kill 100 men in about 30 minutes. “How many other people can claim that?” says Copeland.