The notion of London – or any great metropolis – as sacred space is hardly new, but it is, by definition, problematic and protean. Visualising a Sacred City reflects this ambivalence in both its structure and subject matter. Theologian Alison Milbank takes Dante as a guide and a symbol of our journey through this jostling, transcendent and hellish place: “we should be able to see it … as simultaneously heaven, hell and purgatory”.