Pick a year then go get a subscription to the Tribune online archives and bury yourself in it if you're in Chicagoland. I like to look for the annual church camps and their locations. I read of one near Thatcher woods, but farther east, it was hit by a tornado and tents, goodies and people were flung all about the place. While some of that area is now developed, much of it remains in a city park nearby.
Pay attention to the social pages where available, they present articles on people who were feted, by who and where and the size of the parties as well. Organizational get togethers, such as woodsmen, oddfellows, etc..