Runners have training for months for the 2024 Bank of America Chicago Marathon.
Tens of thousands of runners will participate in Sunday's special event.
The race will start and finish in Grant Park, traveling through 29 neighborhoods along its course.
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Some runners were picking up their last-minute packets Saturday at McCormick Place before they lace up for the big day
In its 46th year, the event has brought both spectators and runners from around the world to the Windy City, like Gabriella Salazar from Peru.
"It's a super exciting feeling because I've been training for this for months," Salazar said.
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Many of the participants have endured months of training, but as for Saturday night, it's about training their mouths, loading up on a lot of carbs before they take to the course.
"Get a big carb load dinner in, hopefully some Italian food, and pass out early, man," said Guy Favazza, a runner from Boston. "For me, it's the mornings. That's the easiest to do it. So, if you wake up, get it out of the way before work whether it's your five-mile runs, ten-mile runs, your 15s. You just got to do it first thing."
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"Tomorrow's going to be a great experience. This is the second year for me. My family's here to support me, and I'm looking to hopefully beat a personal record," said Mark Fortner, a runner from Ohio. "Go out there and have your best run, be safe, and let's go, Chicago."
The race kicks off Sunday morning at 7:30 a.m. in Grant Park.