Lines leading to a vanishing point always seem to make for great composition. This shot was taken on the Lisbon Metro, but I guess it could be any underground train network in the world. The frequency of trains left a lot to be desired, but at least it gave me time to take this shot!
When composing images like this I always try to put the vanishing point on one of the phi points of the golden ratio. I know a lot of people swear by the rule of thirds, but at least 50% of the time I prefer this crop instead.
If you’d like to experiment in Lightroom, go to the Tools menu and select Crop Guide Overlay. Then you can have your pick of different grids to guide your composition. I’m sure that on at least one occasion the golden ratio will be just perfect!