History comes alive at the 30th Annual McConnell's Mill Heritage Festival, sponsored by the Rotary Club of Portersville-Prospect. Come celebrate the historic time of 1852-1928, when the gristmill harnessed the power of the Slippery Rock Creek to grind wheat for bread.

Tour the mill with its original machinery, visit a Civil War encampment, participate in art and craft demonstrations, and enjoy live music. Artists and craftspeople from the local area demonstrate their skills and have their wares for sale. Family activities bring history to life at McConnell's Mill State Park! This event takes place on the last weekend in September every year.