From 1916 until 1956, the Chicago, North Shore, and Milwaukee Railroad ran trolleys from the Roosevelt Road in Chicago up to Milwaukee. Trains traveled along what is now the CTA Purple Line to Linden Street, where the Purple Line now ends. From that point, they went another block up 4th Street, then west on Greenleaf to the Chicago & Northwestern tracks, then ran parallel to those clear on up to Wisconsin.
On Friday, I walked along the North Shore Line's right-of-way for most of the way. (It's now the Green Bay and McClory Trails.) About a month ago, I found a photo on the Trolley Dodger blog of the point where the North Shore Line met the C&NW line, taken in 1950:
Here's the same location Friday:
These days the Wilmette station on the North Shore line is a parking lot. I can only imagine what it must have been like to take a trolley through the streets of Wilmette. I imagine it looked a lot like this: