Driving downtown will be a mess Saturday as several roads around Grant Park will remain closed for the ITU World Triathlon Grand Final, and heavy traffic is also expected for the 30th anniversary Farm Aid concert at Northerly Island.

The triathlon closures started at 5 a.m. Thursday and will continue until 11 p.m. Saturday, according to the city’s Office of Emergency Management and Communications. Jackson is closed between Michigan and Lake Shore Drive; Congress is closed from Congress Plaza to Columbus; Balbo is closed from Michigan to Lake Shore Drive; and Columbus is closed from Monroe to Roosevelt.

In addition to those closures, a temporary traffic hold will take effect on Lake Shore Drive from 5:22-5:32 p.m. Friday and 5:20-5:30 p.m. Saturday to allow triathlon participants to cross from the swim exit to the transition area near Buckingham Fountain, OEMC said.

The triathlon will host more than 6,500 athletes from 62 countries, according to OEMC. They will swim laps in Lake Michigan before competing in the running and biking portions of the race through Grant Park and the surrounding area.

The all-day Farm Aid music festival will kick off at 12:50 p.m. Saturday at the FirstMerit Bank Pavillion at Northerly Island, according to a statement from Farm Aid. The concert will feature performers such as Willie Nelson, John Mellencamp, Mavis Staples and Dave Matthews.

The CTA will provide extra bus service for the concert on the No. 130 Museum Campus and No. 146 Inner Drive/Michigan Express bus lines, the transit agency said in a statement. The extra service will start at 9 p.m. and end about an hour after the concert.