Rockfield, Indiana  Rockfield is an unincorporated community in Rock Creek Township, Carroll County, Indiana. It is part of the Lafayette, Indiana Metropolitan Statistical Area. Rockfield was platted in 1856. The Rockfield post office was established in 1857. District School No. 3 was listed on the National Register of Historic Places in 1988. Rockfield is located at in open farm land south of Rock Creek. A portion of old Indiana State Road 25 and the Norfolk Southern Railway both pass northeast through town. New Indiana State Road 25, the Hoosier Heartland Highway, bypasses town on the northwest.