Interstate 78 in New Jersey Interstate 78 in New Jersey Interstate 78 (I-78) is an east–west route stretching from Union Township, Lebanon County, Pennsylvania to New York City. In New Jersey, I-78 is called the Phillipsburg–Newark Expressway and the Newark Bay Extension of the New Jersey Turnpike. The highway runs for in the northern part of the state of New Jersey from the Interstate 78 Toll Bridge over the Delaware River at the Pennsylvania state line in Phillipsburg, Warren County east to the Holland Tunnel under the Hudson River at the New York state line in Jersey City, Hudson County. The Phillipsburg-Newark Expressway portion of
New York – New Jersey Line War border with New York, which was also located on this branch. But where exactly was this elusive branch of the Delaware River? The East New Jersey Board of Proprietors would lead the effort to establish the location of the northern station point because of the importance of this question in establishing title over much of their territory. Without a firm border, how could grants be made with firm titles; more importantly, without firm titles, how could new business and communities be established? The first attempt to establish the location of the northern border of New Jersey was made in 1684.