Hilliards is an unincorporated village in Washington Township, Butler County, Pennsylvania, United States. The village of Hilliards started out as a mill town, known as Hilliards Mills and became know…Hilliards is an unincorporated village in Washington Township, Butler County, Pennsylvania, United States. The village of Hilliards started out as a mill town, known as Hilliards Mills and became known as Hilliards Station when the Shenango and Allegheny Railroad extended a small route to the community in 1876 to provide service to local coal and oil industries. The village of Hilliards became the southern terminal for the line and provided passenger service for the villages of Eau Claire, Argentine, Annisville, North Washington, Higgins Corners, and Whiskerville until 1935.