Have you ever stopped to notice a manhole cover in Carnegie? Or wondered who made repair parts for train locomotives? Or tried to invent a pair of mechanized scissors? The Thomas Carlin's Sons Foundry did! They manufactured these items and many more, right here along River Avenue between 1893 and 1916. Located on the lot in front of you, the Foundry cast iron into individual items, small tools, complex machinery, and engines for a variety of industries. Thomas Carlin's Sons Foundry even repaired and sold train locomotives, and was a self-described specialist in "the installation of complete brick manufacturing plants."
Thomas Carlin, and Irish immigrant, founded the family business on Sandusky Street in 1861. His sons, Thomas, William, and John grew the company by moving it to River Avenue, where they sold cast iron products to famous regional clients such as H.J. Heinz, H.C. Frick, the B&O Railroad, and the Pennsylvania Railroad. They also shipped products throughout the country and internationally as far as Japan.
Though the Thomas Carlin's Sons Foundry was not a large company, it is representative of dozens of similar foundries in and around Pittsburgh during the region's Iron Age, before steel became the metal of choice. Like most other foundries, Thomas Carlin's Sons was close to the river and to the railroad,
providing inexpensive methods of transportation. Unlike many other foundries, this one had very little storage and expansion space, which eventually led to its decline.
When excavating the site in 2007, archaeologists found remnants of the foundry's foundation walls around the machine shop and warehouse, the clay and cinder foundry floor, and a variety of brick floors within the machine shop and warehouse. Today, nothing is left of the Foundry except the vestiges of its products, like the manhole covers, still visible in and around Pittsburgh. These artifacts are now silent testaments to the region's once colossal iron and steel industry.