Haverford Township Historical Society
The Powder Mill Valley along Cobbs Creek was for nearly 200 years a center of manufacture. Early grist and saw mills were followed by fulling and dyeing mills. The Nitre Hall Powder Mills, which gave the valley its name, were built by Israel Whelen shortly after 1800. Our young nation had growing needs for explosives, and the Nitre Hall mills prospered, with an output of 800,000 pounds during the War of 1812. Nitre Hall produced a quality and quantity of black powder in the U.S. regarded as second only to the famous Dupont Mills on the Brandywine in Delaware. After the powder mills closed around 1840, Dennis Kelly bought the property and converted buildings to the manufacture of textiles.
Today’s Nitre Hall, the home of Whelen’s on-site partner, William Rogers, who acted as powder master, is the only intact building remaining from the industrial era of the valley. The brick-floored ground level was converted to an apartment for caretakers in the 1980’s. No one lives in Nitre Hall anymore. It serves as a museum and home to the historical collections of the Haverford Township Historical Society, which looks after it and holds open houses, tours and educational programs in partnership with Haverford Township, the building’s owner. Much work has been done over the years to restore this largely unchanged house and its surrounding area to their original appearance. Most of the house is furnished and displayed in mid-1800s style, with some areas closed off and used by the Society for its collections and research areas.
Nitre Hall is listed on the National Register of Historic Places. It is open to the public on certain Sundays from May through October annually for free docent-guided tours, and by appointment.