It's not quite like scaling Mount Everest or running the Chicago marathon, but climbing 103 floors and 2,109 steps to the Sears Tower skydeck is no small feat.
More than 700 participants from Chicago and its suburbs, and professional climbers from around the country, tested their mettle Sunday in the second annual "Go Vertical" Sears Tower Stair Climb.
Even the fittest contestants broke a sweat.
It took 51-year-old Aurora native Hal Alan Carlson 15 minutes and 24 seconds to finish what is touted as the world's longest urban stair climb. He came in third, making him the top suburban climber.
People of all fitness levels and ages attempted and completed the climb, which raised money for the Damon Runyon Cancer Research Foundation.