The bridge is constructed out of three 46.5" long 1x3" boards ripped from plywood assembled in a "U" shape. The horizontal board serves as the bridge deck that the roadbed and track will be mounted on, while the vertical boards prevent sagging and warping of the assembly:

A closer look at the basic "U" construction of the bridge assembly. The vertical members also serve as guard rails that will prevent a derailed train from "taking the plunge":

The bridge has been set in place to test the fit onto the layout:

The next steps will be to cutout the movable portion of the bridge, attach the hinge to allow this portion to swing up and down, and attach the door bolts that lock the bridge into the closed position.
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