Downtown
Old Allegheny County Jail Museum
Jail museum inside family court, two Mondays a month

The old Allegheny County Jail is the stone building at 440 Ross Street, attached to the courthouse. Family court uses the building now. Two Mondays a month the Pittsburgh History and Landmarks Foundation puts docents inside it, and the public can walk through. The days are the first and third Monday, 11:30 a.m. to 1:00 p.m.
You enter through court security. Cameras stay outside. What you are walking is the jail H. H. Richardson designed in the 1880s: the cells, the yard, and the enclosed bridge that connects the jail to the courthouse. People call that bridge the Bridge of Sighs. The longer history, including the Biddle escape, is on the haunted-history page.
Sources
When
September
October
November
A boxed day is open to the public.
First and third Monday, 11:30 a.m. to 1:00 p.m. Court security is at the door. No cameras.