The Buffalo Line is like a massive living museum of PRR Signaling. The line was resigned for CTC sometime back when the PRR was in charge so neither the PC, Conrail or NS have seen fit to change anything. In fact, most of the relay huts have little keystones on them. Moreover, there are pneumatic interlockings everywhere, even where you wouldn't expect, i.e. at interlockings with only 1 or 2 switch machines.
On my way home from chasing the Fall Foliage express I was able to stop and take pictures at CP-LINDEN, CP-SOUTH LINDEN, CP-RIVER and CP-KASE and I would have hit some more had I not needed to catch a train at Harrisburg.
You can see all the signally goodness at:
http://acm.jhu.edu/~sthurmovik/Railpics/06-10-14a_BUFFALO_LINE_INTERLOCKINGS/-Thumbnails.html
Since then the second track now starts at LINDEN instead of SOUTH LINDEN. Oddly enough, despite the 1980's re-alignment, a pneumatic switch machine was installed.
Anyway...here's a little tour.
This pedestal signal used to be on the through track, but when everything was re-aligned it can only display diverging routes. Still, the lamp for the CLEAR aspect has been retained!