at one point Pittsburgh was the steel capital of the world
the birth of the commercial oil industry was just north of Pittsburgh in the Oil City / Titusville area - can still see remnants when traveling on the Oil Creek State Park trail and the Allegheny River trail … the Drake Well museum (northern end of the Oil Creek State Park trail) in Oil City has some neat stuff … also has a running train / rail road
https://www.traillink.com/trail/oil-...te-park-trail/
.