Portland Cement

Historical marker location:

7248 Tilghman St, Upper Macungie Township, Pennsylvania

( Marker is at the intersection of Tilghman Street and Mill Road/Windsor Drive, on the right when traveling west on Tilghman Street.)

Marker installed: 1947

Pennsylvania was the site of the deadliest nuclear accident in U.S. history. In 1979, a partial meltdown occurred at the Three Mile Island nuclear power plant in Harrisburg, Pennsylvania.