The tracks and alleys are my favourite places in the city. If my destination is accessible via either system then I'll always chose that path over the street. It's amazing how far you can get on the tracks without running into another person, yet you're right in the middle of a populated city. Streets are boring. Everyone walks on the street. Streets are busy and hectic and affected. On the streets people are working at creating a facade. But these other places are like secret, hidden, behind places. No one cares what they look like so they are often constructed piecemeal of discarded bits and pieces. All that rusted tin and old wood. That's where the character is. I love it.
Alleys are in a sense an old system. They don't have alleys in the suburbs. Too bad for them.