A Pennsylvania Railroad Keystone Station sign for FG interlocking tower on the PRR Main Line in Altoona, PA. FG controlled the passenger tracks on the east side of the Altoona station. NOTE: this object is a scenery (building) item. It can be used by placing it next to a building. Based on PRR Drawing Number 78160-A, dated 1926. Developed using Blender 2.79 and TANE SP4 (Build 105766).