The Oxford/ Van Nest Gap Tunnel

The Oxford Tunnel was a key part of the Warren Railroad, which allowed the Delaware, Lackawanna & Western railroad to run all the way up to Hampden, NJ via the Central NJ railroad. To this day I'm not sure why they decided this would be a worthwhile endeavor, considering the abundant mountains and valleys of Warren County. However, the history of the American Railroad network has proved to be full of arrogance and determination. The Warren Railroad would be no exception. James Archibald and McAllister & Wiestling were the engineers tasked with figuring out just where this new branch of John Blair's Railroad was to go. 

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As the planned line made its way to Oxford in 1853 the engineers discovered the most efficient path would involve blasting a tunnel through Oxford Mountain to reach the Van Nest Gap. A lack of resources and time required that a temporary track be installed to get things rolling while they worked on blasting out the tube.  While the nearby Manunka Chunk Tunnels along the same line were finished in two years, the Oxford tube took nearly nine. Trains finally started using the passage in the autumn of 1862.

As the line aged towards the new century, traincars were getting larger and larger. This presented a problem for the tunnel; the existing tracks didnt allow enough clearance for the bigger cars. Instead of spending any more time and money to expand the tunnel, the company chose to replace the double track with a gauntlet track instead. This allowed at least a single train to make it through the tunnel. The portals were also reinforced with concrete at the same time.

The gauntlet was only a temporary solution. Shortly after it was installed the DL&W Railroad began work on the Lackawanna Cutoff. The new line would allow trains to bypass the backup that was caused by the reduction in traffic at Oxford and shaved eleven miles off the journey.

The former right of way through Warren County began to be referred to as the Lackawanna "Old Road". It was mainly used for freight traffic, occasionally seeing use as a backup when the Lackawanna was delayed or impassable. Trains stopped using the Oxford Tunnel sometime in the 1970's or 1980's. The old road changed hands and saw a few partial revivals which makes nailing down an exact date tricky. I'm sure an area railfan will have an answer in the comments before long. Without regular maintenance the ancient drainage systems that once kept the tunnel manageably damp had become blocked, leading to flooding throughout the passage. By 1984 the marble dedication plaque was precariously exposed and in danger of falling. A team of men consisting of local enthusiasts volunteered to retrieve it, and after doing so it was re-installed at the historic Shippen Manor. 

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The first major collapse inside the tunnel is reported to have happened in 2007. That's according to premier New Jersey hiker and historian Mike Helbing. Mike grew up in the area, and is as credible a source as any. The man has hiked and bushwacked his way through more disused former rail bed than anyone I know. A second collapse in 2018 left the tunnel in precarious shape. Route 31 goes directly over the west portal, meaning any further deterioration posed a serious risk to anyone traveling over it. Helbing tried to raise the alarms, but local officials seemingly quashed his concerns. A shoddy fence was installed on the east portal in an attempt to keep people out, but the state owned west portal remained unobstructed for months until they also installed an equally shoddy fence. 

There have been no updates on the status of the tunnel in the last few years. Considering Oxford Mountain is pockmarked with collapsed and flooded abandoned mineshafts, it stands to reason the township and DOT will continue to ignore the problem until they can't anymore. I can only hope nobody is traveling on the roadway above when the next collapse occurs.