Outside the Central Guard Tower, from the South side, with a view of downtown Philadelphia
Since inmates never left their cells during solitary confinement, originally there was no central guard tower. Later, after solitary confinement was abandoned, a wooden central guard tower was constructed using inmate labor. Although the wooden tower was solid, it was judged to be a fire hazard. A new tower sheathed in corrugated metal was completed by October 1951. The new tower had four flood lights, some of which are visible here, and a swiveling spotlight on the roof operated from inside.