The Pennsylvanian is a 444-mile (715 km) daily daytime Amtrak train running between New York City and Pittsburgh via Philadelphia. The trains travel across the Appalachian Mountains, through Pennsylvania's capital Harrisburg, the Pennsylvania Dutch Country, suburban and central Philadelphia, and New Jersey en route to New York. The entire train ride takes about 9 hours total: 1.5 hours between New York and Philadelphia, 2 hours between Philadelphia and Harrisburg, and 5.5 hours between Harrisburg and Pittsburgh.

The Philadelphia to Harrisburg Main Line is a rail line owned and operated by Amtrak in the U.S. state of Pennsylvania. This is the only electrified Amtrak line in the United States outside of the main line of the Northeast Corridor. The line runs from Philadelphia, where it meets the Northeast Corridor at Zoo Junction at milepost 1.9, west to Harrisburg, where electrification ends. The Main Line is part of the longer Keystone Corridor, which continues west to Pittsburgh along the Norfolk Southern Railway's Pittsburgh Line. This section is sometimes referred to as "Keystone East" and is part of Amtrak's Keystone Service.