Perched above the turquoise waters of the Adriatic in the sun-baked south of Croatia, Dubrovnik is arguably the best- preserved walled city in Europe — and, ironically, that’s partly because of a war. Just a decade ago, those walls were under siege, pounded by Serb artillery. Restoration was badly needed, and Unesco stepped in — but their funding came with strings attached: the character of the city was to be strictly preserved, facades would remain unmodernised, and shop signs barely visible. And it’s worked: Dubrovnik today is more splendid than ever before.

The main draw is the old town, a medieval fortress that was tarted up in the baroque style after a violent earthquake in the 17th century. Freed of all motorised traffic, its pale limestone buildings, topped with their distinctive terracotta tiles, look so perfect that, from certain angles, the whole city resembles a film set.

The main thoroughfare, Stradun — its cobbles polished smooth as glass by hundreds of years of promenading feet — bisects the old town from Pile Gate in the west to the harbour in the east, where fishing boats jostle for space with local ferries. From May to October, tables and chairs spill onto the pavements, and there are few better ways to pass a balmy afternoon than to sit out beneath a parasol nursing a drink and watching the parade of handsome, swaggering locals.

The main decision you have to make on a Dubrovnik short break is whether to base yourself inside or outside the city walls. Although there are obvious advantages to staying in the old town, most hotels lie outside, where it’s often quieter as well as being closer to the beaches. The best location is Ploce, just to the east and a 10- to 20-minute walk into the old town. Whichever option you pick, a few days as an extra on the Dubrovnik film set are hard to beat.

Get your bearings: only the most jaded tourist could fail to be wowed by the walk along the top of the towering city walls. The views are astonishing: across acres of orange rooftops, over cathedral, clock tower and cloisters, up to the craggy mountains inland and down to the glistening sea. The walk also offers intimate glimpses into the lives of local people, as the walls pass opened shutters, trails of underwear on washing lines, and neat gardens where you can almost reach out and pluck the oranges from the trees.

It is not only the views that will take your breath away. The walk is steep and surprisingly vertiginous, particularly if you climb every rampart and turret, and although the whole circuit covers just 2km, it can easily take an hour to negotiate. There is also plenty to think about: it was behind these walls that the population of Dubrovnik withstood a nine-month siege by Serbian troops and artillery in 1991-2, sometimes without power or running water.

Entrance to the walls costs £1.40. Buy a ticket at one of the two entrances — beside Pile Gate or beneath St Nicholas’s Church — and go either when it opens at 9am or for the last hour before closing at 6.30pm, when the crowds thin and the light softens to a golden glow.

Relics, relics everywhere: start at the cathedral, which appears unremarkable until you get to the treasury, just to the left of the altar. It contains more than 180 relics, including a leg and an arm of St Blaise, the city’s patron, and his skull encased in a fetching Byzantine crown decorated with gold and enamel filigree. It’s not all grisly: there is a lovely Madonna and child, apparently painted on the bottom of a barrel, possibly by Raphael.

Step out of the cathedral past the Rector’s Palace, which was closed for renovation when I visited in May, and into Gunduliceva Square, where you’ll find a daily morning market of vegetables, local cheeses, fish, flowers and figs. Before the war, the women tending the stalls all wore national costume. They have now abandoned that tradition and are resisting requests by city authorities to dress up again for the sake of camera-toting tourists.

Around the corner is the main square, Luza, flanked by St Blaise’s Church, the sumptuous gothic facade of Sponza Palace and a 15th-century clock tower. Just to the north is the Dominican monastery and museum, which houses a must-see collection of religious art and literature including an 11th-century Bible and a 14th-century copy of book by Thomas Aquinas. Among the relics is one of St Dominic’s middle fingers, which is raised in a way that would nowadays be considered very rude. For a short period during the siege of 1992, the well in the cloisters was the city’s only supply of fresh water.

At the other end of Stradun from Luza, beside Pile Gate, is a Franciscan monastery that is also worth a look. Relics include the tiny, silver- encrusted skull of St Ursula, and, allegedly, a splinter of Christ’s cross. There’s also a pharmacy that dates from 1317, said to be the world’s oldest.

Hit the beach: Dubrovnik has a surprisingly pleasant pebble beach, 10 minutes’ walk away from the centre. The facilities were being rebuilt in May, but the water was crystal clear (there is no heavy industry along this coast). Locals go after lunch, so if you want it to yourself, go in the morning.

Take to the water: even with only a short time in Dubrovnik, you should spend at least a day exploring one of the islands dotted along the coast. The nearest is Lokrum, a haven of tranquillity, pine forests and rocky beaches, which is said to be where Richard the Lionheart was shipwrecked on his way home from the Crusades.