Colin O'Brady Antarctica Mission: American Man Becomes First to Complete Solo, Unaided Trip Across Frozen Continent

An American has become the first person to travel across Antarctica unaided and alone, in a treacherous 54-day trek. "I did it!" 33-year-old Colin O'Brady told his family through tears at the end of his 932-mile mission, his wife, Jenna Besaw, told The Associated Press.

O'Brady started the unaided journey he dubbed "The Impossible First" on November 3. He reached the South Pole on December 12, in what his website described as a "major milestone."

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He completed the final 80 miles of his challenge in a 32-hour push, which started on Christmas morning. On Instagram, he described that experience as "some of the most challenging hours of my life" but "some of the best moments I have ever experienced."

His expedition partly earned its dramatic title because O'Brady had no resupply or food caches to retrieve along the way, despite having to consume about 8,000 calories a day. He had to survive on what he could pull on his sled, starting out with a 400 pound load. To stay true to his aim of completing the challenge unaided, he pledged to not accept food, fuel or gear at any stage. O'Brady's crossing was completed on foot, unassisted by machinery, dogs or kites.

Over the course of his journey, O'Brady endured temperatures of -40 Celsius in a desert where high winds reach up to 200 miles per hour, causing wave-like ridges to form on the snow. O'Brady documented his experiences on Instagram and Twitter, and a GPS tracker meant fans could follow his every move online.

"Not only am I pulling my 300lb sled all day, but I'm pulling it up and over thousands of these sastrugi speed bumps created by the violent wind," he wrote in an Instagram post on 12 November. "It's a frustrating process at times to say the least."

By day 37, he told his followers he beleived the journey had transformed him. "I'm no longer the same person I was when I left on the journey, can you see it in my face?" he wrote.

"I've suffered, been deathly afraid, cold and alone. I've laughed and danced, cried tears of joy and been awestruck with love and inspiration."

Besaw, who was among O'Brady's loved ones awaiting his return in his home city of Portland, Oregon, told The Associated Press her first call with her husband after he completed his mission was emotional. "He seemed overwhelmed by love and gratitude, and he really wanted to say, 'Thank you' to all of us."

And while her husband predicted he would crave a cheeseburger when he reached the finish line, he had actually been pining after fresh fish and salad because he had eaten so much freeze-dried food, she said.

Before setting off, O'Brady said in a YouTube video that he hoped his expedition would encourage others to live out their dreams. "I've been preparing my mind, my body, my spirit, for something they say is impossible. To show you that nothing is impossible. This project is for anyone who's been told their dreams are impossible. Take your first step, be possible."

Colin O'Brady, the Oregonian who was the first person to cross Antarctica alone and unaided. Colin O'Brady/Instagram