Interstate 78

Number of Miles 145

• Pennsylvania - 78 miles
• New Jersey - 66 miles
• New York - less than 1 mile

Major Cities Along the Route

• Allentown, Pennsylvania
• Newark, New Jersey
• New York City, New York

Intersections with other Interstates

• Interstate 81 in Bordnersville, Pennsylvania[?]
• Interstate 95 in Newark, New Jersey

Spur Routes

• New York City, New York - I-278, I-478, I-678, I-878

Notes In New Jersey, I-78 forms the Newark Bay Extension of the New Jersey Turnpike. Between the end of the Turnpike and the Holland Tunnel, I-78 continues for five blocks on 12th and 14th streets of Jersey City, New Jersey. This section of I-78 has traffic lights; I-70 and I-78 are the only two main-line interstate highways with this feature. Originally, I-78 was going to cross Manhattan, but didn't because putting six lanes of asphalt across New York City, New York is prohibitively expensive.

None of I-78's spurs actually intersect it. A 7.2 mile gap exists in Union County, New Jersey between I-78 and I-278. At 0.72 miles, I-878 is the shortest three-digit interstate in existence; it is unsigned. (I-395 in Maryland is the shortest signed three-digit interstate -- see Interstate 95.)

In the future, I-78 may continue along United States Highway 22 from Harrisburg, Pennsylvania to Pittsburgh, Pennsylvania, and ultimately, to Interstate 77, and maybe even Interstate 70. If it had happened, it would form a corridor between New York City, New York and Columbus, Ohio.