Thanks to everyone who posted a guess.

Two of you had it correct: Alice Moulton-Ely and Maddie Dugan.

Many people guessed Waukegan Road, which was a good guess given the time period (1925) and trying to determine what major roads had been constructed by then.

The photograph shows Deerpath looking east from the present-day Route 41. It was taken in May 1925, while the Skokie Valley route of the North Shore Electric Line was being constructed.

We will post another photo this coming Sunday, but with a new twist that I will reveal on Friday in a special announcement on the site.

Thanks again for your participation and feedback. It's been terrific.