What is the setting of Trainspotting by Irvine Welsh?

Trainspotting takes place primarily in the Leith area of Edinburgh, presumably in the late eighties. Certain parts of the story take place in London, where characters regularly travel for an escape or to broker a heroin sale. At one point, Renton actually attempts to move down to London, but he eventually returns to Leith. The city has a strong hold on natives.