U.S. Federal Route 22 runs along a expressway through Allegheny County, except for a short segment between the junction with Interstate 376 and the Allegheny/Westmoreland County Line. U.S. Rt. 22 passes through the following town in Allegheny County. Pittsburgh U.S. Rt. 22 is multi-plexed in Allegheny County. U.S. Rt. 30, from near Imperial to near Edgewood. Interstate 376, from near Carnegie to Monroeville.