Indian-born Fauja Singh earned a spot in the World Record Book for his accomplishment.
It took Singh more than eight hours to cross the finish line - more than six hours after Kenya's Kenneth Mungara won the event for the fourth straight year - and he was the last competitor to complete the course.
But his time wasn't nearly as remarkable as the accomplishment.
Event workers dismantled the barricades along the finish line and took down sponsor banners even as Singh made his way up the final few hundred yards of the race.
Family, friends and supporters greeted Singh when he finished the race.
Fauja Singh - 100 Years Old Torrento Marathon Runner Set World Record 2011 Video