A massive concrete arch railroad bridge in western New Jersey, built by the Delaware, Lackawanna & Western Railroad in 1908. Paulins Kill Viaduct was built as part of the DL&W's Cut Off Line, between Hopatcong, New Jersey, and Stroudsburg, Pennsylvania. The Cut Off was 28.5 miles long, and was flat as a table top, with a ruling grade of 0.5 percent. It replaced a more roundabout 40-mile route between the two points, thus saving 20 to 60 minutes of travel time. To maintain the line's flat profile, a 115-foot-high bridge had to be built across the Paulins Kill River, near Hainesburg, New Jersey.

The Paulins Kill Viaduct contains seven concrete arches and spans a total length of 1100 feet. At the time of its completion, it set a record for the amount of concrete used in a single structure. It crossed the Paulins Kill River valley, as well as the main line of the Lehigh & New England Railroad.

Several miles to the west, another massive concrete arch viaduct was used to span the Delaware River. It crosses Interstate 80 on the New Jersey side, and is best viewed heading eastbound. The DL&W later made similar improvements on their mainline in northern Pennsylvania, and constructed an even larger concrete arch bridge called Tunkhannock Viaduct, which had ten arches and was almost a half-mile in length.

Paulins Kill Viaduct carried the mainline passenger and freight traffic of the DL&W until 1960, when the railroad was merged into Erie-Lackawanna. The bridge changed ownership again in 1976 and passed to Conrail. Conrail preferred to use the ex-Erie mainline to the north and the ex-Lehigh Valley line to the south, and in 1983, train operation over Paulins Kill ceased. The trackage between Hopatcong and Stroudsburg was pulled up, and the right-of-way sold to a developer.

For many years there was interest in commuter rail service between New York City and Scranton, Pennsylvania, which would use the abandoned Cut Off Line. These myths became reality in December of 2001, when the state of New Jersey purchased the right-of-way for $21,000,000. Paulins Kill Viaduct will once again see trains, this time the commuter operations of New Jersey Transit. Service is expected to be restored by 2004.

As a side note, Paulins Kill Viaduct is accessible by foot. It is located about half a mile south of New Jersey Route 94 in the middle of nowhere near Hainesburg, and a rather steep 115-foot climb will take you to the top of the bridge. The view is impressive to say the least.