American adventurer Colin O’Brady finished his crossing of Antarctica on Wednesday, becoming the first person to accomplish the feat alone and unaided.

O’Brady reached his destination, the Ross Ice Shelf, 32 hours after leaving his camp on Christmas Day. He did not sleep while covering the final 80 miles of his journey, which he called a continuous “Antarctica Ultramarathon” in an Instagram post.

“While the last 32 hours were some of the most challenging hours of my life, they have quite honestly been some of the best moments I have ever experienced,” O’Brady wrote on Instagram. “I was locked in a deep flow state the entire time, equally focused on the end goal, while allowing my mind to recount the profound lessons of this journey.”

O’Brady, 33, reached the Ross Ice Shelf on Day 54 of his journey. He skied 932 miles across Antarctica while towing a sled filled with supplies that weighed around 400 pounds at the start of his journey. He never had to refill his supplies or use a kite, according to The Mercury News.

O’Brady and British adventurer Louis Rudd started their separate expeditions on the same day, Nov. 3, hoping to accomplish the same feat. However, Rudd still had about 70 miles left in his journey when O’Brady finished Wednesday, per The Mercury News.

Rudd, 49, announced in April that he was planning to make the solo expedition. O’Brady shared his plans for his trek in October, reports The Mercury News.

Henry Worsley, a friend of Rudd’s, attempted the expedition in 2016. He came within 126 miles of the finish but was airlifted from the ice and later died. Another British adventurer, Ben Saunders, tried the trek in 2017 but gave up at the South Pole, according to The New York Times.