Stretching 776 feet along the shore of the Ohio River below the town of Ambridge, the American Bridge Company works employed 12,000 people at its peak. The company built trusswork for the San Francisco Bay Bridge, Empire State Building in New York City, and Sears Tower in Chicago, among its many projects. The exterior of the Main Bridge Shop mimics half timbering, but uses exposed steel and concrete instead of wooden timbers and plaster. Daylight floods the cavernous interior through the glazed sawtooth pattern of the roofline and long, multipaned windows. The site, now an industrial park that accommodates other large metal buildings, also includes the original launches for the landing ship tanks made in the factory during World War II.