Dillinger Tunnel: Upper Milford’s Hidden Landmark

Dillinger Tunnel is Upper Milford’s only train tunnel. 

In fact, it’s the only train tunnel still used in Lehigh County.

For former Vera Cruz resident Joe Benner, 85, the mention of Dillinger Tunnel triggers memories of a close call from the 1940s.

"I got caught in the tunnel when a train came," Benner said. "Thank goodness for the area around the shaft -- that's where I stayed until the train passed."

Benner also recalls that at the age of 11 or 12, he and his buddies would "hop the train at the tunnel, because it was going slow enough, and ride it to the next station… Dillinger Station -- just a short distance from the tunnel."

It's illegal now for people to enter, but the Dillinger Tunnel has endured the changes of time -- a 136-year-old historical landmark south of Vera Cruz dug through solid mountain granite and still used for freight runs.  Located off Churchview Road-- less than a mile from the east side of Vera Cruz Road and around a bend, it cannot be seen from the roadway.

The 1,793-foot tunnel -- about a third of a mile -- was completed in 1875 on the Reading Railroad’s Perkiomen line, which ran from Emmaus to Philadelphia. 

“Regular freight and passenger rail service between Allentown and Philadelphia via the Dillinger Tunnel commenced on October 11, 1875,” said Rick Bates, archivist and publications editor, Reading Railroad Heritage Museum, Hamburg (Berks County).

The 16-mile line, now used three days per week, is owned by East Penn Railways and runs from Pennsburg to Emmaus Junction, joining the Norfolk Southern line.

In a 1951 centennial history of Vera Cruz, R. Paul Dries wrote in his article “The Vera Cruz-Dillinger Tunnel” that about 300 Irish laborers worked from four directions -- “one group from each outside end worked towards the middle; two groups from the center worked towards each outside end.”

A vertical shaft placed midway in the tunnel, through which stones and rocks were hoisted to the surface, became an air vent allowing smoke and gas to escape. Above the tunnel, a cement wall eight-feet high surrounded the top of the shaft to prevent anything from falling into it. The wall and shaft are still there hidden among trees and underbrush.

At the tunnel’s entrance, traffic from the Northeast Extension of the Pennsylvania Turnpike is heard crossing 40 feet above, as water drips from between rocks, creating small rivulets along the tracks.   

At one time, the Dillinger Tunnel had watchmen patrolling 24-hours-a-day, checking for anything that could block the tracks.

“During World War II there were guards at both ends of the tunnel to protect it from sabotage,” according to a July 1978 article in the former Allentown Evening Chronicle.

And in the early 1960s, it was considered for use as a fallout shelter to protect people from radiation in the event of nuclear war, the story said. However, it was never stocked with supplies because there was no storage area. The tunnel could have held 2,639 people, according to a civil defense official.

In 1990, Dillinger Tunnel was closed due to a rock slide. “A wooden support frame inside the tunnel was accidentally ripped out several years ago by an oversized rail car. Mother nature's annual freeze-and-thaw cycle then loosened rocks and boulders inside the tunnel, which came crashing down on the tracks,” an article in The Morning Call said at the time. The story said the tunnel was reopened after being closed temporarily for more than two weeks.