Biarritz or Lyon?

This is the widest gap between the two cities. Biarritz is built around its sand: the Grande Plage below the casino, the surf beach of the Côte des Basques, the sheltered Port Vieux cove and several more kilometres of beach running north through Anglet. The Atlantic is fresh and often rough, so swimming happens between the lifeguard flags.

Lyon has no sea at all. Locals use the supervised lake at Miribel-Jonage on hot days, and the Rhône quays are only for sunbathing. For clear water you need a day out to Lake Annecy or the Lac du Bourget.

Both cities have a cuisine of their own, but Lyon's runs deeper and wider. Its bouchons, the legacy of the Mères lyonnaises, generous set lunches and the stalls of Les Halles Paul Bocuse make eating a reason to come in itself, with Beaujolais and the northern Rhône wines close by.

Biarritz is narrower. It offers Basque cooking around its own covered market, pintxos at the counter, fish from the Bay of Biscay, Bayonne ham and gâteau basque. That is good eating for a small resort, but there is little beyond Basque and French cooking.

Lyon has far more to see. The Roman theatres on Fourvière, the traboules of Vieux Lyon, the workshops and murals of Croix-Rousse and a major fine-art collection in a former abbey fill several full days, and the Institut Lumière adds the birthplace of cinema.

In Biarritz the main sight is the resort itself: the imperial villa, the Art Deco casino, the Belle Époque villas and the footbridge out to the Rocher de la Vierge. The aquarium and the Cité de l'Océan round it off, but serious museums mean leaving town.

Lyon gives you a fuller night out, and in every season. A large student population keeps the wine bars of the Presqu'île, the pubs of Vieux Lyon and the bar and club barges on the Rhône busy, and there is a real electronic music scene. Weeknights outside term time can still end early.

Biarritz goes out mainly in summer, with wine and pintxos around Les Halles, sundowners above the Côte des Basques and a few clubs plus the casino. Out of season most evenings finish after dinner, and the bigger nights are across the border in San Sebastián.

Biarritz's outdoors is mostly the ocean. It has surf breaks for beginners and experts, paddleboarding and kayaking when the swell drops, and a cliff path south towards Spain. The green Pyrenean foothills begin within half an hour, and La Rhune and the hills around Sare are good for walking.

Lyon's outdoor life is gentler and more urban. You get car-free river quays for running and cycling, the Parc de la Tête d'Or, and the Monts d'Or and Beaujolais hills close by. The real mountains of Chartreuse, Vercors and the Alps are an hour or two away by car.

Both make excellent bases, and the difference is in the kind of day out. From Biarritz many trips cross a border: San Sebastián, Hondarribia and Bilbao in Spain, Bayonne and Saint-Jean-de-Luz on the French side, and Basque villages such as Espelette and Ainhoa inland. Several of these are easier with a car.

Lyon's trips lean towards wine and old towns, almost all in France. There is Roman Vienne a short train ride away, medieval Pérouges, the Beaujolais and the Burgundy towns around Beaune, and Annecy and the Alps to the east, with Geneva at the far edge of a day.

Both work equally well with children, but they make very different trips. Biarritz is a summer beach vacation, with surf lessons, the calm Port Vieux cove for the youngest, and the aquarium and ocean centre for rainy days, though the big waves need watching.

Lyon is a city stay built around the free zoo, pedalos and pony rides in the Parc de la Tête d'Or. Add the dinosaur skeletons at the Musée des Confluences, Guignol puppet shows and the funicular rides. In both places the hilly lanes are hard going with a pushchair.

Biarritz is small enough to cover on foot, but it is a hilly walk, with steep streets and steps between the town and the beaches. Buses and coastal trains reach Bayonne and the border, but the Basque villages and the Pyrenees really need a hire car.

Lyon is simpler. Most of the sights are on the Presqu'île between the two rivers, which is flat, and the metro and funiculars spare you the climbs to Fourvière and Croix-Rousse. You can see the whole city without driving.

Lyon has the deeper shopping. Chain stores line the main streets of the Presqu'île, luxury labels gather around Place des Jacobins and Part-Dieu has a large mall. Silk from the weaving tradition and the designer workshops on Croix-Rousse are the more personal finds.

Biarritz is a pleasant place to browse rather than a reason to come. It has fashion boutiques, surf shops, striped Basque linen, espadrilles and chocolatiers, but no department stores.

Neither city is cheap, but Lyon is easier on the budget. Its hotels are reasonable for a large city, except during trade fairs and the Fête des Lumières, and set lunches in the bouchons are good value.

Biarritz charges resort rates, especially in July and August, when rooms book up early. Eating at the market bars, coming outside summer or staying in Anglet or Bayonne all help, but a beach vacation here stays expensive.

Lyon has much more on stage. It has an opera company and ballet under the glass vault of the Opéra, a national orchestra, grand old playhouses and cellar jazz clubs. In summer the Nuits de Fourvière festival stages concerts, theatre and dance in the Roman theatres, so there is a programme on most nights.

Dance links the two cities. Biarritz has its own ballet company at the Gare du Midi and an autumn dance festival, but beyond that there are mostly touring shows and summer seafront events. Lyon matches its dance with the Maison de la Danse and the Biennale.

Biarritz is the place for a proper cure. It has been a sea-bathing town since the nineteenth century, and its large seafront spas offer heated seawater pools, algae wraps and programmes lasting several days. Outside July and August the town itself slows right down.

Lyon offers a different kind of rest: Sunday mornings by the Saône, time in its big park and a handful of hammams and day spas. For thermal baths you take a day trip to Aix-les-Bains.