The running world descended on Chicago once again Sunday as roughly 45,000 runners took to the streets for the 2015 Bank of America Chicago Marathon.
WATCH: A couple tied the knot at the eighth mile marker during the 2015 Bank of America Chicago Marathon.
Viewers sent us their photos of the best runner outfits they saw at the 2015...
After 26.2 grueling miles, the Chicago Marathon ends in a split second as runners cross the finish line.
People run the Chicago Marathon for many different reasons, but one Chicago man ran the race not just for himself, but for his son, who never got to run the marathon he was training for.
Viewers sent us some of the best signs they saw at the 2015 Chicago Marathon.