When the air horn sounds the start of the LaSalle Bank Chicago Marathon on Oct. 7th, Australian lightning bolt Benita Johnson, Kenyan racehorse Felix Limo, and several others of the world’s fastest runners will jockey for records and Olympic trial qualifying times. But the vast majority of the event’s 45,000 runners do it for less grandiose, but no less noble, reasons: a cancer survivor to celebrate her remission, a father to make a memory with his teenage son, a physician to prove to his patients that he, too, can drop 40 pounds. They’ll all gather at the starting line in Grant Park near Columbus and Jackson—energy gels pinned to their shorts; feet duct taped to ward off blisters—and set off across 12 neighborhoods toward the silver lining: the Mylar blanket at the finish line, the sign of a goal accomplished.

For more information, go to chicagomarathon.com

Photograph: Anna Knott; Styling: Kami Bremyer