Historic Sites

An Iron Baron’s West Philadelphia Castle

Nathaniel Burt wrote of Philadelphia iron-making entrepreneurs such as the Whartons, Brookes, Rutters and Potts: “Along with the New York patroon and the New England shipowner, he does provide something of a landowning equivalent to offset the more purely trading wealth of the region’s old families.” 1 Thus the Whartons became the lords of Batsto, the Brookes’ of Birdsboro, and the Potts’ of Potttown and Pottsville.

The house at 3905 Spruce Street, built by the iron baron Joseph Potts in 1876, befits the residence of businessmen who helped make Pennsylvania a center of the American industrial revolution. As landowners and founders of the iron-mill towns of Pottstown and Pottsville, they also possessed something of a feudal mystique.

When Old Philadelphia families started crossing the Schuylkill into West Philadelphia in the years following the Civil War, the social rule of thumb of living between Market and Pine continued, with families clustering around the newly-moved University of Pennsylvania. 3905 Spruce sits comfortably within these prescribed boundaries, although in the 1870s West Philadelphia was still largely rural and undeveloped.

3905 Spruce is built in a Ruskinian Gothic style that mirrors Penn’s nearby College Hall. The mansion, designed by the Wilson brothers, on one hand possesses elements of a feudal castle with its pointed windows, chiseled chimneys, and slate roof. At the same time, the house was a showcase for the products of the workshop of the world, with its cast-iron roof decorations and conservatory and polychrome exterior brick walls. The interiors were a tour-de-force of the Philadelphia woodcarvers art, boasting a massive three-level carved oak central staircase, pocket doors of birds-eye maple, and fireplaces supported by snarling griffins and bordered with tiles.

Potts’ son William graduated from Penn in 1876 – the year his father’s house was completed, and subsequently became a very generous financial supporter of the school. By 1917, the neighborhood had become less fashionable, and Penn was swallowing up many surrounding properties around the Potts castle. That year, William Potts donated the family mansion to Penn and decamped, like many of his social compatriots, to the Main Line suburbs.2 The building was used subsequently housed Penn’s International House and later the WXPN radio. During those years, the house suffered rough treatment and deferred maintenance.

But at least the Potts mansion was left standing. Most of the compounds of the Philadelphia aristocracy belonging to the Drexels, Clarks, Swains, and Sinnotts have been replaced by denser row house development or razed by the University of Pennsylvania. Remnants of this enclave of industrial wealth, such as St. Mary’s Episcopal Church and two Drexel mansions currently used as fraternity houses, now sit high and dry in a desert of concrete high rises and brick plazas known as the “Superblock.”

Today, the weary Potts mansion stands stripped of its ornamental features such as the domed roof on the cost iron conservatory, the glass-enclosed porch facing Spruce Street, and its port-cochere. Its brick walls and slate walls are smeared with grime, and the chimneys lean precariously. Nonetheless, it was benevolent neglect that allowed much of the house’s extraordinary interior detailing to survive intact. The house built by Joseph Potts is one of the few survivors of the Golden Age of West Philadelphia. Its association with one of the regions most distinguished industrial families, and the high quality of construction and craftsmanship makes Potts mansion at 3905 Spruce makes one of the most significant and underappreciated historical and architectural jewels of University City.


1 Nathaniel, Burt The Perennial Philadelphians (University of Pennsylvania Press), 1999. 180.