U.S. Route 22 (US 22) is an east–west United States Numbered Highway that stretches from Cincinnati, Ohio, in the west, to Newark, New Jersey, in the east. In Pennsylvania, the route runs for between the West Virginia state line in Washington County, where it is a freeway through the western suburbs of Pittsburgh, and then runs east to Easton and the New Jersey state line in the Lehigh Valley region of eastern Pennsylvania.
Much of US 22 in Pennsylvania follows the route of the historic William Penn Highway. The portion from the Pennsylvania Route 66 (PA 66) interchange near Delmont east to the Interstate 81 (I-81) interchange near Harrisburg is the main part of Corridor M of the Appalachian Development Highway System, although a large portion near the center of the route has not yet been upgraded to a four-lane divided highway.
Between Fredericksburg and just west of Allentown, US 22 runs concurrently with I-78. From Allentown to the New Jersey state line, the route is a freeway named the Lehigh Valley Thruway.
Route description West Virginia to Pittsburgh US 22 enters Pennsylvania from West Virginia in Washington County, heading east as a four-lane freeway named William Penn Highway. The route runs through rural areas with some development, curving northeast and then east again before coming to a partial cloverleaf interchange with PA 18 near The Pavilion at Star Lake. Past this interchange, the freeway continues east and crosses Raccoon Creek before curving southeast and reaching a diamond interchange with Maple Grove Road that serves Bavington, Pennsylvania.
Following this, US 22 heads east again and comes to a three-level diamond interchange with the PA 576 toll road.
US 22 enters Allegheny County and immediately reaches a partial cloverleaf interchange with the northern terminus of PA 980, where it also passes over the Montour Trail. From here, the freeway continues east through rural land with some development to a partial cloverleaf interchange with Kelso Road that provides access to Noblestown. The route curves northeast and reaches a partial cloverleaf interchange with US 30 and the northern terminus of PA 978.
At this point, US 30 heads east in concurrency with US 22. US 22/US 30 run east as a four-lane freeway through suburban areas, coming to a partial cloverleaf interchange with Oakdale Road that serves Hankey Farms. Farther east, the freeway has a westbound exit and eastbound entrance with McKee Road that provides access to the borough of Oakdale to the south. From here, US 22/US 30 turn east-northeast and reach an interchange that connects to Old Steubenville Pike, Bayer Road, and Montour Church Road. The freeway comes to an interchange with I-376, where US 22/US 30 head southeast concurrent with I-376, and PA 60 begins by heading east (south) at-grade along a four-lane divided highway.
I-376/US 22/US 30 head southeast as the four-lane Penn-Lincoln Parkway, reaching an interchange with Ridge Road. The freeway comes to a westbound exit and eastbound entrance with Campbells Run Road, where it widens to six lanes. The highway curves to the east and meets I-79 at an interchange.
Past this interchange, I-376/US 22/US 30 narrows to two lanes eastbound and head into the borough of Rosslyn Farms, turning southeast and coming to a westbound exit and eastbound entrance with Rosslyn Road that serves Rosslyn Farms. The freeway crosses into the borough of Carnegie and reaches a bus-only eastbound exit and westbound entrance connecting to Pittsburgh Regional Transit (PRT)'s West Busway before passing over a Pittsburgh and Ohio Central Railroad line. The highway passes over Chartiers Creek and another Pittsburgh and Ohio Central Railroad line as it leaves Carnegie and comes to the PA 50 interchange.
I-376/US 22/US 30 narrows to four lanes, passing under a Wheeling and Lake Erie Railway line and curving northeast into the borough of Green Tree. The freeway reaches the PA 121 interchange, where it gains a third westbound lane, and heads east, entering Pittsburgh and coming to a westbound exit and eastbound entrance with Parkway Center Drive.
The highway turns north and reaches a westbound exit and eastbound entrance with US 19, where US 19 joins I-376/US 22/US 30 on the Penn-Lincoln Parkway. Within this interchange, the road has an eastbound runaway truck ramp and passes under a ramp carrying both directions of US 19 Truck.
The freeway widens to six lanes and passes under a Wheeling and Lake Erie Railway line before reaching an interchange with PA 51, where US 19 Truck joins the Penn-Lincoln Parkway from PA 51 and US 19 splits from the Penn-Lincoln Parkway by heading north along with PA 51. Past this interchange, I-376/US 22/US 30/US 19 Truck narrows to four lanes and passes under Mount Washington in the Fort Pitt Tunnel.
After emerging from the Fort Pitt Tunnel, the freeway passes over Norfolk Southern Railway's Mon Line and PA 837, coming to a westbound exit and eastbound entrance that connects to northbound PA 837. The Penn-Lincoln Parkway heads onto the Fort Pitt Bridge, a double-decker bridge carrying four lanes in each direction, and passes over CSX Transportation's Pittsburgh Subdivision railroad line and the Monongahela River as it heads into Downtown Pittsburgh at Point State Park and comes to an interchange with the southern terminus of I-279, where US 19 Truck heads north along I-279 and I-376/US 22/US 30 continue east along the Penn-Lincoln Parkway. The I-279 interchange also includes eastbound exits and westbound entrances with Boulevard of the Allies/Liberty Avenue and Fort Duquesne Boulevard that serve Downtown Pittsburgh. The four-lane freeway heads east-southeast between Downtown Pittsburgh to the north and the Monongahela River to the south, reaching a partial interchange with Stanwix Street with no eastbound exit. The highway heads under the Smithfield Street Bridge and comes to an interchange with Grant Street, where it widens to six lanes. I-376/US 22/US 30 pass under the Panhandle Bridge carrying PRT's Pittsburgh Light Rail line and then the Liberty Bridge before the lanes split as it reaches a westbound ramp to Second Avenue north of the South Tenth Street Bridge and south of the Duquesne University campus.
Past this, the highway continues east between urban areas to the north and the Monongahela River to the south, with the Three Rivers Heritage Trail in the median. The freeway comes to an interchange connecting to PA 885 and Forbes Avenue north of the Birmingham Bridge, at which point the trail leaves the median of the freeway and the river heads further south from the freeway. I-376/US 22/US 30 head southeast, with the Three Rivers Heritage Trail parallel to the south, and reaches a westbound exit and eastbound entrance with PA 885. The highway turns east away from the trail and passes over the Allegheny Valley Railroad's P&W Subdivision line. The freeway comes to an interchange with Beechwood Boulevard before it narrows to four lanes and passes under the southern portion of Squirrel Hill in the Squirrel Hill Tunnel. Past the tunnel, I-376/US 22/US 30 head through wooded areas and pass over Ninemile Run in Frick Park. The highway leaves Pittsburgh as it comes to an interchange with Braddock Avenue that serves the boroughs of Edgewood and Swissvale. The freeway continues east through suburban areas in Edgewood, passing under Norfolk Southern Railway's Pittsburgh Line and PRT's Martin Luther King Jr. East Busway. I-376/US 22/US 30 turn to the northeast and head through a corner of the borough of Braddock Hills before entering the borough of Wilkinsburg. In Wilkinsburg, the freeway comes to an interchange with the southern terminus of PA 8, where US 30 splits from I-376/US 22 on the Penn-Lincoln Parkway by heading southeast at-grade on Ardmore Boulevard.
Pittsburgh to Hollidaysburg Past this interchange, I-376/US 22 continue northeast through suburban development, crossing into the borough of Churchill and reaching an eastbound exit and westbound entrance with Greensburg Pike. From here, the freeway narrows to four lanes and curves east, coming to an interchange with PA 130. The highway widens back to six lanes and continues southeast, reaching an interchange serving the western terminus of US 22 Business (US 22 Bus.) and PA 791, where it turns to the east and leaves Churchill. I-376/US 22 continue east through suburbs and the road enters the borough of Monroeville upon crossing over Thompson Run and a Union Railroad line. The freeway curves southeast and comes to an interchange providing access to the eastern terminus of US 22 Bus., PA 48, and the Pennsylvania Turnpike (I-76) at the Pittsburgh interchange. At this point, US 22 splits from I-376, which ends at the Pennsylvania Turnpike (I-76), and continues east along William Penn Highway, a four-lane divided highway with at-grade intersections. The road runs through suburban development, curving southeast and reaching an interchange with the western terminus of PA 286 that consists of an eastbound exit and westbound entrance, with the westbound exit and eastbound entrance provided by an at-grade intersection with a short connector. Past PA 286, the route winds to the east.
US 22 leaves Monroeville and enters the borough of Murrysville in Westmoreland County, where it continues east through suburban areas along William Penn Highway, a four-lane divided highway with occasional jughandles. The road curves to the east-southeast and passes over the Westmoreland Heritage Trail and Turtle Creek. The route continues past a mix of rural areas and development, passing to the south of the borough of Export and crosses Turtle Creek again before leaving Murrysville. US 22 curves east and comes to a single-point urban interchange with PA 66 south of the borough of Delmont. Past this interchange, the road runs east-northeast through rural areas with occasional development, turning east and coming to an intersection with PA 819 in Five Points. The route continues east and reaches a junction with US 119 near Shieldsburg. At this point, US 119 turns east to run concurrent with US 22 along William Penn Highway. The road comes to a bridge over Loyalhanna Creek within the Loyalhanna Lake National Recreation Area and enters the borough of New Alexandria. At this point, the two routes pass north of developed areas of the borough and reach an intersection with PA 981 along the northern border of New Alexandria. From here, US 22/US 119 continue northeast through rural land with some development, passing to the north of Keystone Raceway. The road curves to the east and comes to a junction with the northern terminus of PA 982. Past this intersection, the two routes run through more rural areas, curving back to the northeast.