Actually it’s just down Fleet Street. First Irish pub in London (c. 1700), first pub outside Ireland to serve Guinness. Possibly the inspiration behind the song, at least I used to tell people that on the tour-bus. Well, it is a long way from Piccadilly and Leicester Square, if you really need a Guinness. Personally I don’t really like the stuff. Too much iron; turns your poo black, and leaves you open for an attack by mutant villain Magneto.