You can easily walk from one end of the city to the other in fourty minutes. In other words – the dodgy areas rub shoulders with the rest of the city – and I would go as far as to say that you’re never far from somebody shooting up heroin.
From here: http://photito.wordpress.com/2011/02...o-heroin-city/
I've lived in Oslo since 1994 and can vouch for this. In my previous neighborhood (which isn't downtown or even located centrally) I personally came across (and had to report) two instances of heroin-related deaths. Drugs are everywhere.
Not really "unique" by anybody's standards (and as such probably irrelevant to this thread), but the first thing to drop into my mind when I saw your headline, as sad as that is.