Manunka Chunk Tunnels

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It was 1856 when John Blair opened the "Warren Railraod" that cut across Warren County before crossing over the Delaware River. The line had two tunnels and a number of bridges. Construction on the Manunka Chunk tunnel took just two years. The swift completion of the 938 foot long tunnel was a result of the soft shale composition of the rock. By comparison, construction on the Oxford Tunnel to the south took 8 years. 

By 1869 a second bore was opened and the line was double tracked. The completion of the second bore also only took 2 years. The Pennsylvania Railroad's Belvidere and Delaware Division joined the Delaware, Lackawanna and Western line at Manunka Chunk, though only the DL&W used the tunnels. The DL&W connected Hoboken to Buffalo, NY. The "BelDel" ran from Trenton and ended at Manunka Chunk.

In 1876 the two railroad companies joined forces and built both a passenger and freight station, as well as a signal tower. The popularity of the passage was short lived however. By 1911 the Lackawanna cut off opened to the north, diverting traffic away from the DL&W rail line. Two years later a heavy rain storm washed out many rail lines in the area, including the lines at Manunka Chunk. The ensuing flood obliterated the station and knocked over the tower. The structures were never rebuilt.

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Tracks were removed from the eastbound side of the tunnel in 1948 due to lack of traffic on the line. Passenger service had been discontinued by this point, and the line was only used for freight. 

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By the mid to late 1960s more flooding had caused the tunnels to become underutilized. The line was officially abandoned in the 1970s, and the tunnels have sat crumbling ever since.

A number of collapses have all but assured that the passageway will never see rail service again.