The blob at the edge of Italy

Forget the Restaurant at the End of the Universe; the Cafe at the Centre of the World is grander, more genial and much easier to reach. The Caffe San Marco rests heavily on a prominent corner of Trieste's most bourgeois boulevard. Customers make a theatrical entrance through a doorway that possesses the scale and ambition of a proscenium arch. You immediately become part of the drama being played out at the Pinteresque pace of the creakiest old waiter.

Once your pulse subsides from the shrieking Lambretta wars on the streets outside, take stock of the set. Heavy tables are stained to a uniform darkness by a century of immersion in a fine mist from coarse cigarettes. Stern, high-backed chairs glare at a bloated leather Ottoman. The furnishings are upstaged by the well-polished bar, whose shelves support a global binge of bottles in all manner of alarming shapes and shades.

The players are equally heterogenous - in age, appearance and gender. Giggling students slurp drinks in primary colours; men whose faces are the colour of cafe au lait and as creased as croissants play out their last few moves across a doddery old chessboard. The ensemble is multiplied to infinity by a platoon of tall mirrors, you feel as if all Europe has converged on a corner of Trieste.

Indeed, Europe does just that, as it has for centuries. Everyone knows what Italy looks like, but peer closely at the map and you see that the territory seeps a little beyond the natural border. That blob contains Trieste and its hinterland.

The precise frontier was fixed only in 1954, when Italy's dispute with Yugoslavia was finally settled. In those days you could turn left for state Communism, or right for capitalism, from Trieste's main street. Now Yugoslavia has crumbled along with Communism, everyone is a capitalist - and most of them congregate at the central market.

Remarkably, the main commodity is the same as it has been for decades: blue denim. Ten years ago, wild tales circulated on the Inter-Rail circuit about the risks and rewards of the Yugoslav jeans trade. Smuggle a few pairs across the frontier, and you could live on the coast for a fortnight on the profit. Nowadays Serbs and Croats, Bosnians and Slovenes barter and bargain over jeans whose provenance and cut are equally questionable.

A ramble around the city's heart is a confrontation with Trieste's many pasts. The dominant suit is pompous Austro-Hungarian, a kind of Budapest- on-Sea. When the Hapsburgs sought a maritime link with the world, they happened upon a quiet port at the head of the Adriatic. The existing old hillside settlement was left to one side (and continues to be - the modest medieval huddle seems in slow collapse). Like Renaissance Lego, a mercantile city sprang up by order of the EmpireCacophonous resonances abound, and the chorus of cultures drew James Joyce here. The writer constructed his walk around Dublin in Ulysses while swimming in a middle European soup.

The city's dimensions are not merely ethnic. In pre-history, Trieste took a geological hammering. Ancient limestone hills rise sharply from the sea. Where the city streets slam into the stone, a network of gigantic staircases tempts the visitor up to a plateau to appreciate the arc of the Adriatic. If you prefer not to walk, then the most entertaining public transport in Europe will lift you halfway to the sky for 50p.

At sea level, it looks like an ordinary tram - a humble timber-trimmed carriage weary from decades of donkey-work. Just as you wonder how so frail a thing could scale a steep gradient, it rounds a bend and meets a slope that resembles the launch stage of a particularly malevolent roller- coaster. Much shouting and shunting takes place while an extra locomotive is bolted on the back. One heave and the ensemble starts to creep up the mountain.

The world changes quickly, with commerce giving way to viniculture; some fine vines cling to these slopes. Each village seems sleepier than the last, as demonstrated by the increasing number of snoozing, scraggy cats. Then into your peripheral vision creeps the final, glorious act of imperial madness.

Miramare is Italy's greatest folly, dreamed up by a commensurately implausible junior Hapsburg by the name of Maximilian. He decreed that elaborate gardens should rise above a rocky coastline and march towards a castle that is almost childlike in its calculated castellations. The poor chap was dispatched to become Emperor of Mexico at the height of Latin revolutionary fervour, so died before he could see the triumph of turretry that shoulders its arrogant way into the Adriatic.

In the course of a weekend in Trieste you may not meet any marauding Mexicans, but you will encounter just about everyone else. James Joyce was, I hope, sipping a cappuccino in the Caffe San Marco when he wrote, "Trieste remained unmoved and unscathed by the Revolutions and Convulsions around her, and in fact became a City of Refuge to the Stranger."

Simon Calder reports from Trieste for 'The Travel Show' on BBC2 at 9pm tomorrow.

SIX ESSENTIALS: TRIESTE

Italian connection: fly to Venice on Alitalia, British Airways or one of several charter airlines; a fare of pounds 180 return is quoted by the Italian Flight Centre (0181-748 1333) for travel in early June. From Venice airport, take the bus to Mestre station (15 minutes, pounds 1), then the train (two hours, pounds 7) to Trieste.

Slovenian connection: fly from Heathrow to Ljubljana on Adria Airways (0171-437 0143) for pounds 241 return, and take a bus (two hours, pounds 10) to Trieste.

Modest accommodation: check in to the Pensione Centrale, in the middle of the city at Via Pochielli 1 (00 39 40 639482), where you pay pounds 12 per person per night.

Tram trip: there is only one tram route remaining in Trieste; it starts in the centre and wends up to the village of Opicina. The fare is 1,200 lire (50p).

More information: Italian State Tourist Office, 1 Princes St, London W1R 8AY (0171-408 1254).

Italian alternatives: read more Italiana in the travel pages of the Independent Weekend on Saturday.