Billy Goat “Underground” is a variously maligned term of approbation or opprobrium, but for Sam Sianis’ longtime burger house, it’s simply descriptive. On Lower Michigan, beneath the shopper-worn pavements of the Mag Mile, fabulous cheeseburgers and cold pints have outlived the notoriety of Saturday Night Live reruns from the 1970s-“chizborger, chizborger,” anyone? -And it remains the kind of Chicago classic that friends from other lands will keep emailing you for more details about. Last we heard, there was nothing like it in Sydney, Vancouver or Williamsburg.
