Do a Google search of "Weird Missour", "Weird Illinois", "Weird Indiana", "Weird Ohio", Weird Pennsylvania, etc, and then see what attraction are along your route. The "Weird USA" series is absolutely awesome! You'll discover some of the strangest things right next to you, you never knew were there!
Whenever we go camping, I always check out "Weird whatever" and see what's in the area! We've seen some pretty goofy stuff, and usually does not cost anything!
For example, pretty much all my life I've seen the Pink Elephant at Fortville, Indiana on Highway 67, about 15 miles outside the I-465 loop around Indianapolis. I guess I took it for granted, until it appeared in the book "Weird Indiana". Then I HAD to go back and get photos of it for myself. Who would have guessed. I've come to appreciate this fellow now! He's just sitting there, in front of this liquor shop. Absolutely free to look at! Weird hum?