When I originally thought of train music, I thought of songs about the big overland express trains, or the steam-powered locomotives of history.  Those are the trains that come into play at the turning points of life.

But Tom Waits is much more an explorer of the low-amplitude drama of everyday, below-the-median life.  And the trains in that sphere of existence are more likely to be subway than bullet.
https://www.youtube.com/watch?v=hZhW76LAnTY

This song, like a lot of Waits’ work, was more popular in a cover version.  Rod Stewart had a hit with it.
https://www.youtube.com/watch?v=q6yk9wWNB08

And for good measure, here’s Mary Chapin Carpenter, who sang Grow Old Along With Me for my new love and me, twenty years ago last month.
https://www.youtube.com/watch?v=gqkru7jlMAI