The Heritage Discovery Center in the Cambria City neighbourhood covers the other major strand of Johnstown's story: the immigrant steel workers who built the city's industrial economy in the late 19th and early 20th centuries. At its peak, the Cambria Iron Company (later Bethlehem Steel) employed tens of thousands of workers, drawing waves of immigrants from across Central and Eastern Europe — Ukrainians, Poles, Slovaks, Hungarians — who settled in distinct ethnic neighbourhoods that still define different parts of the city.
The center's exhibits explore daily life in these communities, the dangerous conditions in the mills, and how successive generations of immigrant families shaped Johnstown's culture. It is run by the Johnstown Area Heritage Association, which also operates several other heritage sites in the area. Worth pairing with a walk through Cambria City itself, where many of the original workers' churches and houses survive.