An American has become the first person to complete a solo hike across Antarctica. Colin O’Brady, from Portland, Oregon, just finished the astounding 930-mile endeavour. The trek took him almost two months — 54 days to be precise. He completed it without any external assistance whatsoever. That means no dogs or machines to push his 375 pounds sledge. It was just him, and the freezing emptiness.

O’Brady faced temperatures of -40 degrees Fahrenheit, sky-rocketed when the there was wind (which there was often), and elevations between 7,500 and 9,000 feet. To be able to keep pushing toward his objective, O’Brady had to consume around five litres of water per day — he didn’t carry the water; instead, he had with him 55 pounds of fuel to start fires in order to melt ice.

Food was probably the biggest concern for O’Brady. Before the journey, it was estimated that O’Brady would need an average of 7,000 calories per day. The fact that he would have to carry everything, meant that efficiency was the key. So, a lot of buttery porridge, specially designed energy bars, and freeze-dried dinners, among other food options.

“Is it a successful expedition if you get to your very last day and you’re eating your last day of food? Or is it a successful expedition if you get to the end of your project and you’ve got, like, five to seven days of food left on your sled? And it’s funny, because people come really strongly down on either side,” he said as he was preparing for the trek.