Never try to sing anything you don't understand, that's a good principle. Though I can't think of many songs which are more straightforward in saying what they mean than this.

In a dirty old town, instead of courting amidst fields and woods and running rivers, the way you might in a lot of songs, you have to do it in between factories and gasworks, and down by the old canals that you find in old industrial towns. So that's what the guy in the song is doing - but he's dreaming of a future where things get better and the dirty old town is torn down and a splendid new town is built instead. And at the same time the dirty old town stands for the whole system that needs changing.

"This guy doesn't even seem to know where he is... Is it the gasworks or the factory??? " Well, gasworks and factiories both have outside walls, otherwise the roof wouldn't stay up. So he's in the streets where those walls run, and down by the old canal, where the barges used to collect and deliver for the factories. Those are the places he meets his girl - lovers lane, but it's in back alleys.

It's a song from a time and a viewpoint where people tended to think that the way to make things better was to tear down the old and put up the new, and that the new buildings would inevitably mean a new and better life, and it was all more straighforward.

The irony is that when people sing it now the buildings they often have in mind as the key features of the dirty old town, which need pulling down, are the very buildings that were put up to replace the older ones. I live in a New Town, built from the 50s on, but when people here sing this song they tend to set it here in their minds.