Every crawlspace is an adventure. I don’t see that many in Pittsburgh, mostly basements and so I don’t know if that biases things, but often Pittsburgh crawlspaces are a mess. In the older houses I spend all my time in, a crawlspace exists in because it was an addition they hit rock and gave up digging or both. Below is the entrance to the crawlspace.
It is a stone foundation. Above, the foundation stones were in disarray, water from a roof leak had eroded the mortar between the stones and rotted the end of two joists–someone shimmed a joist at the top of the photo.
Above is knob and tube wiring is frayed and degraded.