Let's make this birthday one to remember.

67 years old (Born on January 12, 1958)

Happy Birthday, Mark Allen! Six-time Ironman World Champion, legendary endurance athlete, and the only guy who makes swimming 2.4 miles, biking 112 miles, and running a marathon look like a casual weekend hobby. Your epic battles in Kona—especially that unforgettable "Iron War" victory in 1989—still inspire athletes worldwide to push their limits (and question their sanity).

Here's wishing you another year filled with victories both big and small. May your birthday cake be carb-loaded enough to fuel another championship run—or at least get you through blowing out all those candles! Keep inspiring us all; you're truly timeless!