Aix-en-Provence or Carcassonne?

Neither town is a beach destination, and the sea is a day out from both. The real difference is the kind of swimming you get. From Aix you drive to the Mediterranean around Marseille, where the swimming is in small, rocky or pebbly coves on the Côte Bleue and in the calanques near Cassis. They are beautiful but crowded in August, which is why many visitors simply use the pool.

Carcassonne has gentler water. The sandy, lifeguarded Lac de la Cavayère is a short drive from the Cité, and Gruissan and Narbonne-Plage, about an hour away, are long, shallow sandy beaches that suit children better than the Provençal inlets.

Aix eats better. Its food follows the Provençal market every morning on Place Richelme, with goat's cheese, olives, herbs and vegetables, then long terrace lunches of daube, tians and grilled fish with Coteaux d'Aix rosé. Calissons from the old confectioners are the sweet to take home.

Carcassonne's table is narrower and heavier: cassoulet on almost every menu, with very good Corbières, Minervois and Limoux wines at fair prices. The catch is location, since the set menus inside the Cité are uneven. The better meals are down in the Bastide around Place Carnot and the covered market.

These two are equally rewarding for sightseeing, but in very different ways, and each takes about two days. Aix is a town of refined streets: the plane-shaded Cours Mirabeau, the honey-coloured mansions of the Mazarin quarter, a fountain on nearly every square, and Cezanne's studio, family house and quarries, with the Musée Granet for paintings.

Carcassonne rests on one overwhelming monument. The double-walled Cité has its fifty-two towers, the Château Comtal, a walk along the ramparts and the stained glass of Saint-Nazaire. Below it are the Bastide's medieval grid and the Canal du Midi. Choose Aix for art and townscape, Carcassonne for a medieval fortress.

Aix is livelier after dark because of its students. The bars around Place des Cardeurs and behind the town hall fill on warm nights, and there are a few cocktail bars and small clubs. Even so, it is a terrace town that winds down early.

In Carcassonne an evening means a stroll on the floodlit walls once the day visitors have gone, followed by a glass in a café on Place Carnot. Real clubbing means Marseille from Aix, or Toulouse or Montpellier from Carcassonne.

Aix has the more spectacular countryside on its doorstep. Montagne Sainte-Victoire rises just east of town, the white cliffs and turquoise inlets of the Calanques are within an hour, and there is cycling in the Luberon and the Alpilles and canyon kayaking in the Verdon. The catch is summer, when fire risk often closes the massifs.

Carcassonne's landscapes are quieter and more spread out. There are the beech forests of the Montagne Noire, the garrigue and castle ridges of the Corbières, and rafting in the upper Aude gorges. Its easy outing is the flat, shaded towpath of the Canal du Midi, which is ideal for cycling.

Both towns make excellent bases, and Aix is the better connected of the two. Marseille is half an hour away, the TGV reaches Avignon's papal palace in about twenty minutes, and Arles, Nîmes and the Pont du Gard follow. Gordes, Roussillon and Lourmarin in the Luberon, and Les Baux in the Alpilles, are all within a short drive.

Carcassonne's trips have more of a theme. The Cathar castles of Peyrepertuse, Quéribus and Lastours are the highlight, alongside villages such as Lagrasse, Minerve and Mirepoix. Toulouse and Narbonne are easy by train, while the castles and villages need a car.

Carcassonne gives children more to do. The Cité is a storybook castle with ramparts to walk and summer jousting and falconry, and the lake brings a supervised beach, a water park and an animal park nearby. The steep cobbles and summer crowds are hard going with a pushchair, though.

Aix is safe and pleasant with its pedestrian centre and fountains, but its sights are mansions and museums. Families there tend to rely on a pool and drive out to the zoo at La Barben or the coast.

Aix is the easier town to manage without a car. The old town, the Mazarin quarter and the Cours Mirabeau sit side by side in a mostly pedestrian centre, and regional buses and a local train run often to Marseille and its airport. The one awkward link is the TGV station, which is out on the plateau.

In Carcassonne the Bastide is flat and the station is right beside it, but the Cité is a twenty-five minute walk with a climb at the end. Beyond the trains to Toulouse and Narbonne, a car or a tour is needed for almost every castle and village.

Aix is far better for shopping. The lanes around Rue d'Italie and Rue Fabrot hold French fashion, shoe and homeware boutiques and delicatessens, and on market days there are textile, flower and bric-a-brac stalls. Santons, olive wood and Provençal fabrics make good things to take home.

Carcassonne's Cité lanes mostly sell toy swords and knight costumes, and the Bastide has an ordinary provincial high street. The worthwhile buys are edible: tinned cassoulet, Limoux blanquette and Corbières wine.

Aix is the dearer of the two, and most of the money goes on where you sleep and where you sit. Rooms in and near the old town are scarce and lean towards boutique hotels and country houses, and a lunch on the Cours Mirabeau charges for the plane trees and fountains more than for the cooking. Eating a few streets back, picnicking from the morning market and walking everywhere win some of that back, though a hired car for the Luberon villages soon adds it again.

Carcassonne costs noticeably less overall, and its premium is confined to one hill. Sleeping or dining inside the Cité walls costs more and gives you less for it, while the same evening down in the Bastide comes at an ordinary provincial-town price. Spring and autumn are much kinder to the budget than high summer, and here too car hire is the main extra, because the Cathar castles are hard to reach without one.

Aix is in another league here. Its July opera festival, staged partly in the open-air courtyard of the Archbishop's Palace, is a major event in the opera world. The rest of the year brings touring orchestras at the Grand Théâtre de Provence, Ballet Preljocaj at the Pavillon Noir, and plays at the Théâtre du Jeu de Paume.

Carcassonne's moment is also July, when the Festival de Carcassonne puts concerts and theatre on the open-air stage inside the Cité. Bastille Day adds fireworks over the walls. Outside summer there is little beyond the municipal theatre, and opera means going to Toulouse.

Aix has a real thermal heritage. It was founded on Roman springs, warm water still runs through some of its fountains, and the Thermes Sextius spa sits on the site of the ancient baths. Its unhurried market mornings and long lunches add to the calm.

Carcassonne has no bathing tradition of its own. Its spas are mainly hotel spas, plus the modest spa villages of Rennes-les-Bains and Alet-les-Bains up the Aude valley. Its quieter pleasures are slow walks along the Canal du Midi, best outside the crowded summer months.