The link below is a ride in a passenger coach around the mainline of the Great Northeastern Railway (GNR), "The Standard Railway of the Basement". The video is a few years old, but I still enjoy it. It starts at the suburban station of Terryville, goes through the yards and into the city of Christopolis. After passage through a relatively long tunnel, You are let off at the Terryville station from whence you departed.
When the current improvements being made to the GNR are finished, the managemnt is planning a new rail tour video encompassing all three levels served by the GNR.
So, have your ticket ready, click on the link below and enjoy the ride.
https://www.youtube.com/watch?v=RXWcvnSzFec