Turns out "nabe" is short for "neighborhood" (in the sense, I think, of the community that lives near you); apparently originally used in the phrase "the nabes" to refer to the local theatre.

...the webcam that's trained on Mathew Street, a nabe in Liverpool that houses the famous Cavern Club...

--"Robbery averted via Beatles fan webcam in Liverpool," Engadget, 28 August 2006