Somewhere farther north on this page Whistle Stop says that two factors contributing to the existence of a vibrant folk community are the presence of a college town and a politically liberal environment. Agreed. I think another contributing factor is a community made up of differing cultures which still make their music in public on a regular basis. Music breeds music. It's good for us to be able to hear koto, concertina, and kalimba all in the same community.