CSX super signal bridge in Landsdowne MD

In Landsdowne MD for trains approaching the port of Baltimore on the B&O mainline, there is a signal bridge that is 3 signals high for each track. It replaced an old B&O signal.

How does one read this signal? I noticed tonight a train stopped with a signal of "Green-Red-Red" (top to bottom).

I'd also like to know why there is only one active signal for southbound trains? I thought the B&O was 2-4 tracks.

the signal u described means Clear track ahead and the train can proceed, theres a website with some signal descriptions but i dont have the link, google NORAC signals, and u should be able to find it

Here's a link to NORAC signals. Many of them are the same as CSXT signals.

There's a nice summary chart of CSX signal aspects, names and indications here:

http://www.amdg.ws/Seaboard%20Signals.pdf

That was very interesting. Say, does anyone know what the giant signal bridge protects? Is it an interlocking? I'm rarely there in daylight and it looks like the tracks go from 4-2.

if the tracks do go from 4-2, then yes its a interlocking

There are 4 tracks in Landsdowne with 1 of them a storage track. Tracks 1 & 2 are the tracks of the Capitol subdivision headed to Washington DC and the third is the Old Main Line headed to Point of Rocks. There is track work going on towards Halethorpe that is supposed to extend the storage track down to Saint Denis. It also moves the interlocking down closer to the MARC station in Saint Denis.