We have a classic example near where I live where a double set of trestles was buried and the Plum Creek Railroad which ran underneath the trestles track section was made into a tunnel to allow it to keep operating out to the coal mines in Renton.
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| Before trestle was buried |
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| After trestle was buried |
Seeing how impossible it would be to post guards everywhere along these tracks which had many trestles along them it was decided to bury them so Nazi saboteurs could not place explosives on them and knock them down which could take months to replace instead of a couple days when you just blew up tracks . While another explanation is the trestle where buried to strengthen the trestles to carry heavier loads but if this was the case why was the Allegheny river bridge not reinforced as well as other areas along route . Approach Trestles where also buried about a mile up from these near where a magnificent steel bridge goes over the Allegheny river in Harmarville as a way to help when the new bridge was built . and this bridge was guarded during WWII
Possibly the open sections under a concrete aqueduct which took the B&LE thru East Pittsburgh where also possibly filled in for same reason as where many smaller areas all along the route.
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| East Pittsburgh trestle you can see where openings where |
Thou the Steel mill activity in Pittsburgh has greatly decreased the B&LE is still an active railroad now owned by Canadian National Rail
However the Plum Creek branch stopped service service in early 60's and the abandoned railroad tunnel has now become the workshop for an older gentleman who runs several small oil wells in the area.
