Pittsburgh PAT transit want to build a Subway under the river to the north side and the two stadiums…Now they already have a light rail subway and they want to extedn it under the river whuch would be a expensive undertaking.
The option was to run the trolleys under the Pennslavania Railroad Bridge and another option which i prefer is to bring the trolleys over the bridge in mixed traffic. Since it such a short distance why bother with all the expence?