Pennsylvania Route 103 is a 30.8-mile (49.57 km) long north–south designated state route in the Commonwealth of Pennsylvania. Its primary course is along the south/east side of the Juniata River, while U.S. Route 522 runs along the opposite side. PA 103's southern terminus is an at-grade intersection with US 522 at Allenport in Shirley Township, a bit south of US 522's bridge across the Juniata River in Mount Union. Its northern terminus is an intersection with US 22 Business in Lewistown. It intersects the northern terminus of PA 333 just south of Juniata Terrace.

U.S. Route 522 is a spur route of US 22 in the states of Virginia, West Virginia, Maryland, and Pennsylvania. The U.S. Highway travels in a north-south direction, and runs 308.59 miles (496.63 km) from US 60 near Powhatan, Virginia, to its northern terminus at US 11 and US 15 near Selinsgrove, Pennsylvania. US 522 serves many small cities and towns in the Piedmont, Blue Ridge Mountains, and northern Shenandoah Valley of Virginia. The highway serves the Virginia communities of Goochland, Mineral, Culpeper, the town of Washington, and Front Royal and the independent city of Winchester. US 522 then follows the Ridge-and-Valley Appalachians north and then east through the Eastern Panhandle of West Virginia, a 2-mile-wide (3.2 km) stretch of Western Maryland, and South Central Pennsylvania to its terminus in the Susquehanna Valley. The highway serves Berkeley Springs, West Virginia; Hancock, Maryland; and the Pennsylvania communities of McConnellsburg, Mount Union, Lewistown, and Middleburg.