The bridge pillar used to support some bridge between Schenley Park and South Oakland. There are four bolted routes ones about 5.9, another 5.10, the other two are more difficult (5.11ish?). The blocks are cut stone about 3' by 6'. Amazingly there ae a variety of holds on each route. Jams, pinches, slopers, and of course crimps.
If you live in Pittsburgh its worth one trip. If you go to Pitt, well it may be the only climbing that won't get you arrested.
Getting There
Underneath the Blvd of the Allies. Park at the small playground and then scramble thru broken glass down the hillside. You probably could rap in off the current bridge, but you might meet the boys in blue.