McConnells Mill State Park. Butler Eagle File Photo

Butler County historian Polly Shaw will present a talk on Monday, Sept. 22, about how a gristmill became a state park.

“From Gristmill to Park” will be a look at the three main grist processes that were handled in the operating mill — wheat, buckwheat and corn, which became corn meal or animal feed when mixed with oats.

In its heyday, McConnells Mill was a successful business and one of the first rolling mills in the greater area.

Shaw’s talk will be presented at 7 p.m. in the Evans City Community Room, 204 S. Jackson Street in Evans City. The entrance is the side door toward Washington Street.