U.S. Federal Route 127 is the main north-south highway through Preble County. It runs through the center of the county. U.S. Rt. 127 passes through the following towns in Preble County. Somerville Camden Eaton West Manchester U.S. Rt. 127 is not multi-plexed in Preble County. U.S. Rt. 127 intersects the following highways in Preble County. Ohio State Route 744, at Somerville. Ohio State Route 725, at Camden. Ohio State Route 732, at Eaton. U.S. Rt. 35, at Eaton. Ohio State Route 122, at Eaton. Ohio State Route 726, near Eaton. Interstate 70, near Lewisburg. U.S. Rt. 40, near Lewisburg.