My, isn't Edinburgh beautiful? It just goes to show, there's nothing wrong with revivalism and pastiche – after all, architecture used to be playful
A note from Northern Britain. The word townscape is little more than a century old. Which is not of course to suggest that what it signifies was hitherto unthought of, unconsidered. Pictorial representations of urban topographies' juxtapositions and chance encounters have been made for as long as humankind has been able to wield a pencil.

Even when they're merely background – literal local colour, as in books of hours – townscapes betray a consciousness of the notion that when we build for one purpose (shelter, worship, commerce) we also build for the eyes of others. We may create a visual feast. Equally we may create a visual Big Mac.

I am just coming to the end of two weeks at a feast: Edinburgh. A feast? It's the feast – or rather, feasts, for it is, famously, two cities (at least). And it is that physical division that elevates it above anywhere I can think of. The division is also psychological and intellectual. No other great city of the Enlightenment had a primitive chunk of the dark ages to gape at across a loch, a place where nobody had switched the light on: the old town.

The other set-pieces of rationalism – Bordeaux, Nancy, Paris, for instance – are mostly flat. There is no other city that is so blessed by its site. Bath, Prague, Liege, Genoa and Le Puy are mere contenders.

I am clearly stating the obvious – or, rather, what is obvious to everyone else. I fear that I must be a slow learner. The entire world knows about Edinburgh's beauty. But it has taken me a lifetime to cotton on, a professional lifetime devoted to the architecturally obscure, the tectonically occluded, the urbanistically marginal. Loitering around the fringes has apparently caused me to overlook the core masterpieces.

There is surely a case to be made for bogusness and phoniness. They can often be pragmatically justified

This is a perennial problem. I haven't, for instance, been inside the Louvre in a decade but have often cut through it en route to somewhere off the track like the Musée des Plans-Reliefs in the attic of Les Invalides. And the last time I visited Versailles, Monsieur Pompidou was president, Alain Geismar was on trial for inciting his students to riot and the CRS were on the streets.

Masterpieces make their own rules and Edinburgh is no exception. It prompts me to question an article of architectural faith that I have long held – but then all idées fixes are there to be unstuck. High up the Royal Mile, there is a typically tough block that contains the Radisson Hotel. If you disapprove of it you will characterise it as pastiche or fakery. If you admire it you call it a sympathetic neo-vernacular intervention. I admire it, to my astonishment. It may be that the Scottish vernacular of stone, poivriers and turnpike stairs lends itself to inoffensive copyism.

Or perhaps it is the crassness of the Scottish parliament at the bottom of the Royal Mile that teaches the lesson that humility and appropriateness are qualities that should be displayed for the sake of civility – a word that derives from the same root as city. Close by the UK's premier white elephant, there is, of course, a third way that is guilefully exemplified in a highly crafted block by Richard Murphy Architects. It is both modern and neo-vernacular; it is sympathetic to its surrounds while not pretending to have been designed a few hundred years ago.