CHICAGO (WLS) -- The 42nd Annual Bank of America Chicago Marathon is happening Sunday.
More than 45,000 runners from over 100 countries will participate in the 26.2 mile iconic marathon across the city.
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Marathon organizers will join Chicago officials Thursday morning to host a welcome event for all participants.
The start and finish lines for the race are both in Grant Park on Columbus Drive
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No parking zones will begin at 1 a.m. on Sunday. Residents should pay attention to no parking signs in their areas for full details and timing.
Rolling street closures will take place between 7 a.m. - 3:30 p.m. Roads near Grant Park will be closed for longer periods of time.
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City streets will reopen as the final runners pass through at a 15-minute mile pace.
Marathon officials ask all residents not to attempt to block the race course at any point for the safety of the runners.
Chicago Marathon organizers, city officials to host 'welcome event' for runners