Layout Expansion with container Port

Here's a Trainorders link showing a pic of my 6X7 foot expansion and the future container port. Below the dock and wrapping around the bottom of the expansion is the hidden staging (only one track so far). I recently cleaned up the layout for visitors, so it was a good time for photos!
http://www.trainorders.com/discussion/read.php?f=3&i=29546&t=29546
Njoy!

 

As far as detecting hidden trains, try some sort of break-beam system. Perhaps it could be simple as placing some fiber optics beside the rails at an angle, with a narrow angle LED or something pointing straight at it. Put the opposite end of the fiber optics in the face of the layout, so that the light under the layout lights it up when there's nothing obstructing the beam.

 

Thanks paul! No trackplan to post right now, believe it or not. My layout has been tweaked and modified so much since my original design, I have no current schematic that shows it as it stands right now . I really do need to draw one up...it's pretty interesting. It is so complex, however, that it would probably resemble a bowl of spaghetti with all the different levels. It is intended for continuous loop, mainline running. A train, running at a realistic speed, does not return to the same point for about 6 to 7 minutes! Jon, that is a VERY interesting idea for detection....thanks ! I'll keep that one in mind.