Pitt is great once you're able to stop driving! The trains take you where you need to go for little to no money, the museums and parks are solid and there's plenty of stuff to see and do.
I'm from a Catholic family so I have an apprecation for church design, organs etc. The Cathedral they have is pretty nice and reminds me of ones I've visited in Europe
Oh man! the architecture of that city! Even the newer buildings tended to be nice to look at. But the older stuff is as amazing as any city I've ever been to.
And you wanna talk about nice? Pittsburgh people were so damn welcoming. No city is perfect, but I've never been to any city where I had zero unpleasant encounters. Could have been luck (and probably was, at least in part), but it left a great impression on me.