Eight days in Puglia: the sea on both sides, and a cave city in between

Park outside the old town and walk in through the seventeenth century arch, which is all that survives of the walls. Inside is a few hundred metres of whitewashed lanes with lines of poetry painted on the steps and, at intervals, gaps in the wall where the ground simply stops and there is sea forty metres below.

The town's postcard is a small shingle beach at the bottom of a dry ravine, with cliffs on both sides and an eighteenth century road bridge across the top of it. Swimming there in high season means sharing it with a great many people; going down in the evening when everyone has left is better.

Eat late, on a terrace if you can get one, and start with raw fish.

The cliff under Polignano is hollow. Boats go out from the little harbour for an hour or so and take you along the coast into the sea caves, some of them big enough for the boat to turn round inside, with light coming up through the water and making the roof green.

Do that first thing, when the sea is flattest. Afterwards, the town has a small contemporary art museum in a converted slaughterhouse, which is a better hour than that description suggests, and a statue on the seafront of a singer everybody has heard without knowing his name.

Then find a cove and swim. The coast either side of the town is limestone shelves and small shingle bays and the water is exceptional.

An hour and a half west, off the coastal plain and up onto a limestone plateau of wheat and stone walls. You arrive in what looks like an ordinary provincial town, park, walk two streets, and the ground opens.

The sassi are two amphitheatres of caves and houses cut into the sides of a ravine, stacked so that one house's roof is another's street. The first sight of them from the edge of the modern town is the moment people remember.

In the evening drive round to the far side of the gorge. There is a viewpoint on the opposite rim, on the rough plateau where the shepherds lived, and from it the whole city faces you across the ravine and lights up at dusk.

Give the morning to walking down. There is no plan to the sassi and no reliable map: lanes turn into staircases, staircases turn into somebody's roof, and the only sensible approach is to head downhill and accept that you will come out somewhere unexpected.

Two of the rock churches are the ones to go inside. One stands on a spur of bare rock above the ravine with a second church cut into the cliff behind it. The other is the largest excavated church in the town, with frescoes half stripped away and, in a back chamber, the stone niches where bodies were drained before burial.

In the afternoon cross the gorge on foot if you are able: a path drops from the sassi to the stream at the bottom and climbs the far side to the plateau, where more than a hundred rock-cut churches are scattered among the scrub, several with Byzantine frescoes still on the walls.

Two hours south east, back into Puglia and down the length of the Salento, through olive groves that were until recently the oldest in Europe and are now full of dead trees: a bacterial disease has killed millions of them since 2013 and the landscape is visibly changed.

Lecce arrives as a surprise after that, a compact walled town in golden stone. Start with the building everybody comes for: a church that took a century and a half to finish, with a front of cherubs, animals, fruit and grotesque figures piled up until there is no flat surface left.

Then the cathedral square, which is unlike any other in Italy because it has only one way in. You come through a narrow arch and the space opens out on four sides, a closed courtyard with a seventy metre bell tower in the corner, and at night with nobody in it, it is the best thing in the south.

Lecce's main square has an amphitheatre in it. It was found under the paving in the early twentieth century, only about a third has been excavated because the rest is beneath the buildings around the square, and it seated twenty-five thousand when this was a Roman colony.

A few streets away is a better story on a smaller scale. In 2001 a man renovating a house to open a restaurant dug for a sewage pipe, found a tomb, and kept going for years: Messapian cisterns, Roman drains, a chamber from the age of the Templars, medieval frescoes and a grain store, all stacked under one ordinary terraced house. He abandoned the restaurant and opened the house instead.

In the afternoon, the castle, which is a heavy sixteenth century fortification built by Charles V to keep the Ottomans out and now full of exhibitions and a papier mache museum, which is a genuine Lecce craft rather than a joke.

The Salento is narrow enough that both seas are within half an hour of Lecce, and they are completely different. Drive east first, to the Adriatic, which is rock and cliff and deep clear water, and go as far south as Otranto: a white walled port that is the easternmost town in Italy, close enough to see the Albanian mountains on a good day.

Its cathedral has a floor. In the 1160s a monk laid a mosaic across the entire nave, a tree of life running from the west door to the altar with the months of the year, elephants, a mermaid and King Arthur in it, and you walk on the whole thing. Off the same church is a chapel stacked with the skulls of eight hundred men killed by an Ottoman force in 1480.

Then cut west across the peninsula to the Ionian side, where the coast turns to white sand and shallow turquoise water, and swim before driving back for dinner.

A last morning inside the walls. Lecce has three old gates and a triumphal arch, all within ten minutes of each other, and walking between them takes you round the edge of the old town and past the parts you have not seen.

Buy a pasticciotto, which is warm shortcrust filled with custard, costs about a euro and is what breakfast is here, and one more bag of taralli for the journey.

Brindisi airport is forty minutes away and the car goes back there. Bari is an hour and a half if you are flying from where you started.