Thousands of athletes are taking over Chicago's lakefront on Sunday for the nation's largest triathlon.
The Supertri Chicago brings everyone from first-time competitors to elite pros together for a swim, bike, and run through the city.
The swimming portion was still underway around 8 a.m. The athletes will then transition to cycling and running.
The SuperTri Chicago brings athletes of all skill sets to compete through Grant Park and the lakefront.
The event is two days long, with the kids' triathlon taking place on Saturday. Last year, more than 9,000 athletes competed in the event
Organizers say the event also gives Chicago a boost to the economy.
5 a.m. 8/22; reopens 7 p.m. 8/23: E. Balbo Dr., DuSable Lake Shore Dr. to S. Columbus Dr.
10 a.m. 8/22; reopens 5 p.m. 8/23: N. Lake Shore Dr. / NB Randolph exit ramp.
4 a.m.-1 p.m.: Simmonds Dr., from Montrose Harbor Dr. to Foster Ave.
2 p.m.-7 p.m.: S. Columbus Dr., E. Balbo Dr. to E. Roosevelt Rd.
5 a.m.-noon: Lake Shore Dr. SB lanes, E. Randolph St. to W. Hollywood Ave.
5 a.m -12:30 p.m.: E. Randolph Lower St., S. Columbus Dr. to lakefront.
5 a.m.-noon: E. Lower Wacker Dr., Randolph to State.
5 a.m.-noon: N. Wacker Lower Dr., State to Madison.
5 a.m.-noon: S. Wacker Lower Dr., Madison to Jackson.
