There were several locations in the film but a few outside shots were taken in Gurnee, Illinois (that's outside Chicago) at The River Trail Gardens and Inn located at 36355 Route 41, Gurnee, IL, 60031. It's a motel they used in (I think) that scene where Steve Martin and John Candy have to share a bed? The building doesn't really look the same anymore but you can go see it!
In Planes, Trains & Automobiles, the character of Neal is trying to make it home to Chicago for Thanksgiving.
planes, trains, and automobiles
trains, planes and automobiles
Planes, trains and automobiles.
Milk
Planes, Trains and Automobiles.
Planes, trains and automobiles.
planes, trains, and automobiles
The two main stars of Plains, Trains and automobiles were Steve Martin and John Candy.
planes, trains, and automobiles
A shower ring salesman.
Dylan Baker. Hilarious