By the time construction was complete, the total project cost for the station and associated tunnels was $114 million (equivalent to $2.26 billion in 2018), according to an Interstate Commerce Commission report.

The North River Tunnels carried PRR trains under the Hudson; for some years PRR electric engines also pulled Lehigh Valley Railroad or Baltimore and Ohio Railroad trains to New York.
The East River Tunnels carried LIRR and PRR trains to the Sunnyside Yard in Queens.
As part of the New York Connecting Railroad improvement project, a connection from the East River Tunnels to the New Haven Railroad tracks was also built.
New Haven trains began running through the East River Tunnels, serving Penn Station, in 1917 after the Hell Gate Bridge opened.

The electrification of the New York Tunnel Extension, including the station, was initially 600-volt direct-current third rail.
It was later changed to 11,000V alternating-current overhead catenary when electrification of PRR's mainline was extended to Washington, D.C., in the early 1930s.
In New Jersey the third rail ended at Manhattan Transfer, where all trains stopped to change steam and electric engines.
Two electrical substations were built for the project: one in Harrison, New Jersey, and the other in Long Island City, New York.

After the New York Tunnel Extension opened, some PRR suburban trains continued to serve the Exchange Place station, where passengers could board the PRR ferry, or the Hudson Tube system (later called PATH), to downtown Manhattan.
The ferry from Exchange Place ended service in 1949, and the Exchange Place PRR terminal closed in 1961.

One branch, the freight-only Harrison Branch, split off the line just east of its west end and ran west to a connection with the Delaware, Lackawanna and Western Railroad's Harrison Cut-off and the Erie Railroad's Paterson and Newark Branch.
By the time construction was complete, the total project cost for the station and associated tunnels was $114 million (equivalent to $2.26 billion in 2018), according to an Interstate Commerce Commission report.
The North River Tunnels carried PRR trains under the Hudson; for some years PRR electric engines also pulled Lehigh Valley Railroad or Baltimore and Ohio Railroad trains to New York. The East River Tunnels carried LIRR and PRR trains to the Sunnyside Yard in Queens. As part of the New York Connecting Railroad improvement project, a connection from the East River Tunnels to the New Haven Railroad tracks was also built. New Haven trains began running through the East River Tunnels, serving Penn Station, in 1917 after the Hell Gate Bridge opened.
The electrification of the New York Tunnel Extension, including the station, was initially 600-volt direct-current third rail. It was later changed to 11,000V alternating-current overhead catenary when electrification of PRR's mainline was extended to Washington, D.C., in the early 1930s. In New Jersey the third rail ended at Manhattan Transfer, where all trains stopped to change steam and electric engines. Two electrical substations were built for the project: one in Harrison, New Jersey, and the other in Long Island City, New York.
After the New York Tunnel Extension opened, some PRR suburban trains continued to serve the Exchange Place station, where passengers could board the PRR ferry, or the Hudson Tube system (later called PATH), to downtown Manhattan. The ferry from Exchange Place ended service in 1949, and the Exchange Place PRR terminal closed in 1961.
One branch, the freight-only Harrison Branch, split off the line just east of its west end and ran west to a connection with the Delaware, Lackawanna and Western Railroad's Harrison Cut-off and the Erie Railroad's Paterson and Newark Branch.
New York Tunnel Extension