 It is a modern steel car which remained in service until the 1970s, when cabooses were phased out.Since 2002 the museum has operated a heritage railroad over a 4-mile line along the banks of the scenic Fox River to the Jon J. Duerr (formerly Blackhawk) Forest Preserve.Visitors can board at the Castlemuir depot, on the museum grounds at the north end of the line in South Elgin, or at Blackhawk station, at the south end of the line, adjacent to the picnic grove of the Jon J. Duerr Forest Preserve.