Positano or Saint-Tropez?

The real difference is sand against shingle, and swimming in town against swimming out of town. In Positano you swim right below the houses. Spiaggia Grande and Fornillo are dark grey sand and pebble that drop steeply into deep, clear water, and Arienzo, Laurito and further coves are reached by long stairways or by boat.

Saint-Tropez's real beach is Pampelonne, about 5km of fine pale sand on the Ramatuelle side, with public stretches between the beach clubs and wilder coves at Escalet and Cap Taillat beyond. The sand is softer underfoot and gentler to wade into, but getting there means a drive or a ride, because only small beaches such as Les Graniers are close to the town.

Neither is a place for eating widely, but Saint-Tropez gives you more to work with. Its Provençal table of bouillabaisse, aïoli and rosé from the surrounding vineyards is backed by the Place des Lices market and the tarte tropézienne, so there is local food life beyond the restaurant terraces.

Positano offers memorable long lunches over the sea, with clams, scialatielli and lemon desserts. But the menus repeat from one terrace to the next, and there is little market or street food to vary them.

Saint-Tropez has more reason to step indoors. The Musée de l'Annonciade holds pointillist and Fauvist paintings from the years when Signac painted the harbour, and the maritime museum in the citadel adds to it. With a walk through the lanes of La Ponche, these fill a worthwhile day.

In Positano the sight is the townscape itself, along with the majolica dome of Santa Maria Assunta and the painted Roman villa beneath it, and a couple of hours covers them. The coast's major monuments and museums lie further round the bay.

This is where the two differ most. In summer Saint-Tropez has a famous and moneyed party circuit: afternoon parties at the Pampelonne beach clubs, champagne on the harbour, then clubs with dress codes and table service until dawn.

Positano's evenings are aperitivo with a view and a long dinner, with a few bars and a single cave club at the end of Spiaggia Grande. That suits couples, not anyone wanting a real night out. Both towns go quiet once the season ends.

Both have fine coastal walking, but Positano's setting is the more dramatic. The Path of the Gods runs high above the sea to Nocelle, and steeper trails climb through chestnut woods to ridges over 1,000m. Kayaks and boats explore the grottoes and the Li Galli islets below.

Saint-Tropez's Sentier du Littoral is gentler, following pine-backed coves to the capes of Camarat and Taillat, with the Massif des Maures inland. Its strength is on the water: sailing on the gulf, diving off the rocky points and the national park islands of Port-Cros and Porquerolles. In summer, the risk of forest fires can close trails.

Positano has far more within a day. Capri is half an hour by boat, Amalfi and Ravello are a ferry ride along the coast, and Pompeii, Herculaneum and the Greek temples of Paestum are all within reach. These are places of real historic weight, though most ferries stop outside the season.

Saint-Tropez's outings are pleasant rather than major: the hilltop villages of Ramatuelle and Gassin, Grimaud's ruined castle, the canals of Port Grimaud and tastings at the wine estates, with Porquerolles or Fréjus for a fuller day. The roads jam badly in summer, which makes every one of these trips slower.

Saint-Tropez is the easier of two difficult choices. Pampelonne and Gigaro have sandy, gently shelving water that suits small children, and the old town is flat, small and safe to walk, even if little else is aimed at children.

Positano is built of stairs, which rules out pushchairs, and its pebbly beaches drop off quickly. It works best with older children who love swimming and boat trips.

Both towns are small enough to walk and awkward to leave. Positano's problem is height: walks involve hundreds of steps, a loop bus serves the single road, and in season the ferries from the beach do most of the work, so a car is more of a burden than a help.

Saint-Tropez is flat and compact, but its main beaches are several kilometres out and there is no railway. Most visitors drive, ride a scooter or take taxis, and the gulf road jams in July and August. The passenger boats from Sainte-Maxime and Port Grimaud are the calmer way in.

Saint-Tropez is the better place to shop. The big fashion houses keep summer boutiques in the lanes behind the port, alongside swimwear and jewellery. There are also hand-stitched Tropézienne sandals from old-town workshops, and linen, baskets and pottery at the Place des Lices market.

Positano has a style of its own: loose white linen, printed resort wear, sandals cut while you wait, ceramics and lemon soaps. It is all one look, though, with no markets or wider fashion beyond it.

Both are among the most expensive places on the Mediterranean, and the quieter months only soften the cost. The way to save differs. From Positano, staying in Praiano or Sorrento and coming in by bus or ferry saves a great deal, and May and October are noticeably kinder.

In Saint-Tropez, taxis and parking add to the cost of rooms and harbour terraces. Travellers on a budget stay inland or across the gulf, picnic from the market and swim from the public stretches of Pampelonne.

Neither town has much to attend. Serious opera or theatre means going to Naples from Positano, or a long drive to Toulon or Nice from Saint-Tropez. The difference is in the summer extras. Positano is within an evening's reach of Ravello's classical festival on its terrace over the sea, while Saint-Tropez has open-air concerts at the citadel and the Bravade each May, a centuries-old costumed procession with muskets.

Positano is the more restful of the two, largely because the setting does the work: hotel pools cut into the cliff, slow lunches on terraces and the sea below. It is calmest in May, June and late September, while the stairs and the summer crowds are the drawbacks.

Saint-Tropez also relies on hotel spas aimed at guests, and its high summer is louder, with evenings shaped by the party scene. Outside the peak it slows down to games of pétanque under the plane trees and morning walks up to the citadel.