It's an achievement the young American has been working toward for several years after turning to extreme sports to recover from a freak accident which left doctors wondering whether he would ever walk again.
The ex-financier quit his job in 2008 to pursue sports full-time, reaching Olympic triathlon level and breaking the "Seven Summits" world record. But this Antarctic crossing has been his toughest challenge to date. Several others have died making the attempt.
O'Brady, who calls his mission "The Impossible First,'' set out on Nov. 3 and became the 29th person ever to reach the South Pole solo and unaided on Dec. 13, 40 days into his journey.
However, the final leg of O'Brady's journey was almost undoubtedly his most difficult: The extreme athlete completed the final slog of his almost-two-month mission with an epic 32-and-a-half-hour-long trek, which started early on Christmas Day morning and finished on Boxing Day. In that period alone, he covered approximately 80 miles.
O'Brady described the final push as "some of the most challenging hours of my life." Yet he also said they also gave him a chance to reflect on the "profound lessons" he had learned during his journey.
CNBC Make It took a look at those learnings and how they can be applied to other — less frosty — walks of life.