The Camden Cutoff bypasses the Carrollton Viaduct, but it has to
cross the same stream (the Gwynn's Falls) as that venerable structure.
It does so here via what is listed as the Blue Top Bridge, just south
of where I-95 now crosses overhead. This view looks back SW, away from
the city. According to "Real Stories from Baltimore County History"
the stones used to build the Cutoff, and presumably this bridge, were
hauled from Relay where the Old Main Line was cut into the hill near
the Thomas Viaduct monument.
This is the place the OML should have crossed the Gwynn's Falls originally.
It's far more level, straight and simpler here than at the Carrollton Viaduct.
Rail construction at this spot dates to the 1850s and almost certainly initially
spanned the stream via a Bollman bridge. It's likely this bridge seen
in this photo replaced the Bollman design sometime in the early 1900s. There
are four tracks crossing the water here, three active and the one in the
foreground obviously abandoned some time ago.