»In which Pittsburgh gets it, double bore

The City of Pittsburgh and the Port Authority of Allegheny County are embarking on an ambitious two-bore tunnel to connect the North Side with Downtown Pittsburgh (and the "T": I hope that the new North Side line will properly connect the Downtown and South Side routes at Gateway Center). Now that the North Side is home to new football and baseball fields, and Downtown to a spanking green Convention Center, moving people efficiently and comfortably becomes more important -- despite the bevy of bridges.

Shawn Bennear's Pittsburgh Transit page has excellent photographs of rolling stock old and new (and mod!).