The system carries an average of 227,000 passengers each weekday between Manhattan and northern New Jersey. Those numbers are expected to rise by 25 percent over the next decade.
Officials of the Port Authority of New York and New Jersey say they plan to spend $3.3 billion to add and replace PATH train cars and modernize the system's 13 stations.
The system dates to February 1908, when it was run by the Hudson and Manhattan Railroad. The Port Authority took it over in 1962.
