Not so much a scenario, as a layout with a heap of code behind it.
Based on a fictional English landscape from around 1980, give or take a few anachronisms, your task (if you choose to accept it) is to drive a steam special from the Port Katherine Railway Centre around the mainline network.
Alternatively you could just sit-back and watch the British Rail trains wander around seemingly at random, turning up where you least expect them.
Come on. Own up. Who said 'No change there'? You're not going to be allowed to play with the trains until someone owns up...