The Trenton Cutoff is a 48.0 mile rail line in the U.S. state of Pennsylvania that runs from Morrisville to Thorndale. The line, today used by the Norfolk Southern, is known as the Morrisville Line between Morrisville and Earnest and the Dale Secondary between Earnest and Thorndale.
Built by the Pennsylvania Railroad and opened in 1892, the cutoff served to connect mainline freight traffic from New York City and Harrisburg by bypassing Philadelphia by an alignment that goes through the suburbs north and west of the city.
A low-grade line, the cutoff runs from Morrisville Yard on the Northeast Corridor to THORN interlocking. Between Morrisville and Earnest, the line has active freight service. At Earnest the cutoff connects with the former Reading Railroad. From Earnest west to GLEN interlocking the line is a single track in dark (unsignaled) territory with one freight per day of ArcelorMittal steel traffic between Conshohocken and Coatesville.[unreliable source?]