The Illinois Tollway expects about 2 million drivers to use its tollway system Wednesday alone.
The best time to leave is before 10 a.m.
IDOT said lanes that have been closed for construction will reopen to help with traffic Wednesday through Sunday.
As for those traveling by train, Amtrak said Wednesday is their second busiest travel day of the year.
The rail line gearing up to accommodate a surge of riders passing through Union Station.
Airports will be packed again with holiday travelers.
TSA expects to screen 18.3 million people during the holiday travel period. That's about 6% more travelers than last year.
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TSA reminds all travelers to head to the airport early.