2024 Bank of America Chicago Marathon: In its 46th year, three runners continue to participate in each 26.2-mile race across the city

CHICAGO (WLS) – A big weekend in Chicago begins on Thursday. Runners from all over the world will attempt to run, walk or jog 26.2 miles this Sunday.

The Chicago Marathon Expo kicked off Thursday at McCormick Place, where ABC7 caught up with three strangers who met over the course of the annual challenge.

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Race director Carey Pinkowski opened the exhibit for the 46th annual Bank of America Chicago Marathon. The race now welcomes runners from 140 countries and all 50 states, running 26.2 miles through 29 Chicago neighborhoods. However, only three people can say they have done the first event in 1977 and all since.

Henry Kozlowski is one of these three men. Chicago is the only marathon he has ever run, but he has completed them all.

“I had no idea. I just wanted to do the first run because it was like five bucks and in Chicago,” Kozlowski said.

Only about 5,000 runners took part in the first race, then called the Mayor Daley Chicago Marathon.

More than 50,000 runners are expected at the start on Sunday.

The boys were all in their mid to late 20s when they ran their first marathon. They are now in their mid-70s. These days, training and running are a little more demanding.

Randy Burt, 76, has run 92 marathons, but Chicago was his first.

“I am 29 years old in 1977. I'm thinking, 'I should run one of these before I get over the hill,'” Burt said.

The boys all live in Illinois, but usually only see each other once a year at the Marathon Expo.

The long-time race director introduces her to a group of former Olympians and world record holders.

“Isn’t that amazing?” Pinkowski said. “They trained for 45 years in a row and made it to the start and finish. These are the Iron Men of Chicago. Great guys too.”

George Mueller said training is a little different these days, but he's thankful he can do it every year.

“I still feel the excitement at the beginning,” said Müller.

The record for most consecutive marathons is held by someone who completed it in Boston.

The boys from Chicago have the honor of running every Chicago Marathon. They hope to make it to 50.