Access to layout interior

[mojohn55]

I am planning a 11' x 18' layout with an open middle area. It will be be in a 11' x 18' room with track located along the walls. I am looking for info on how install an access that will swing up or lift out and still maintain track alignment, etc. Any ideas?

[SpaceMouse]

This is a subject that has been addressed quite frequently. I would try the search function on. "Lift-outs", "liftout" "duck-under" etc.