Brittany or Cornwall?

The two coasts are equally good for a beach trip, but the beaches are different. Brittany has wide sandy bays on the south coast around Carnac and Quiberon, pink granite coves at Ploumanac'h, and enormous tidal flats at Saint-Malo and Dinard. The sheltered Gulf of Morbihan gives the slightly warmer swims.

Cornwall is the place for surf beaches, such as Fistral and the long sweep at Gwithian. The turquoise coves of Porthcurno and Kynance Cove are among its best-known views. Wetsuits are more common there, and the big beaches fill during the school summer break.

Brittany eats better. Oysters from Cancale and the Gulf of Morbihan, scallops, buckwheat galettes with dry cider, salted butter in everything and a weekly market in every town give its food real depth. Rennes adds the region's broadest restaurant scene.

Cornwall's best food is fish from Newlyn and the seafood dining rooms of Padstow and St Ives, plus pasties and cream teas. Beyond the harbour towns the choice falls away quickly, and resort menus often cater to the passing summer trade.

Brittany has the denser heritage. The rows of menhirs at Carnac rank among Europe's major prehistoric sites. Add the corsair walls of Saint-Malo, the half-timbered streets of Dinan and Vitré, and the parish closes of Finistère, and you can see historic towns every day for a week.

Cornwall offers single landmarks rather than whole old towns: St Michael's Mount, Tintagel, and the mining engine houses near Botallack. Its own strength is modern art. Tate St Ives and the Hepworth garden have no real equivalent in Brittany, where the museums are modest.

Both regions are quiet at night, and most villages wind down before midnight. Brittany's late nights happen in Rennes, where students fill the bars of Rue Saint-Michel, and in the village fest-noz dances. Cornwall's busiest nights are in Newquay in summer, a surf town with clubs and stag and hen groups, while Falmouth's university gives it a smaller scene.

These are two closely matched Atlantic coasts, each followed end to end by a long-distance path: the GR34 in Brittany and the South West Coast Path in Cornwall. Brittany's extra is its offshore islands, such as Belle-Île, Ouessant and the Glénan archipelago, along with puffins at Sept-Îles and kayaking among the islands of the Gulf of Morbihan.

Cornwall is the place to go for surfing, at Newquay, Bude and Sennen. Seals are common and basking sharks pass offshore in summer, and Bodmin Moor gives it higher, wilder ground inland than Brittany's low moors.

Brittany has far more variety within reach. Mont-Saint-Michel is about an hour from Saint-Malo, boats run out to islands from Quiberon, Vannes and Brest, and Nantes, Quimper and Concarneau make very different outings from each other.

In Cornwall, a day out usually means another harbour town, whether that is Mousehole, Port Isaac or Fowey. They are lovely but quite alike. The Isles of Scilly are the standout trip, though they take a full day.

Both are classic seaside regions for families, built on rock pools, sandcastles and self-catering stays. Brittany's sailing schools, campsites and gîtes suit longer stays, and Océanopolis in Brest covers wet days. Cornwall has lifeguarded beaches for bodyboarding and the Eden Project for when it rains, but its summer traffic is harder on children in the back seat.

Brittany is easier. Fast trains reach Rennes from Paris, regional lines continue to Quimper and Brest, and the toll-free dual carriageways make driving between bases simple.

Cornwall's high-hedged single-track lanes and the scarce summer parking in St Ives and Port Isaac make a car tiring to use. Its branch railway lines are the way round this: staying in St Ives, Falmouth or Looe without a car works well.

Neither region is for fashion shopping. What you bring home is different. Brittany sells Quimper faience, striped sailor tops, salted caramels and Guérande salt, and the Saturday market at Place des Lices in Rennes is the highlight. Cornwall's best buys are pottery and paintings from the St Ives studios, plus surf gear from Newquay.

Brittany is the cheaper of the two, and it stays that way in high summer. Its prices go up in July and August, when rooms around Saint-Malo and the Gulf of Morbihan are in demand. Even so, campsites, gîtes, crêperies and toll-free roads keep a Breton stay moderate when the same weeks in Cornwall get expensive.

Cornwall's costs are higher and add up from more directions. Coastal cottages for the school summer break book out early at high prices, and parking and attraction tickets add to a family's bill day after day. Prices ease in both regions outside the peak, so June or September saves money whichever coast you choose.

The difference here is a living musical tradition against one unforgettable stage. In Brittany, Celtic music is part of village life, with bagad pipe bands and fest-noz dances. Summer brings large festivals, from the Festival Interceltique in Lorient to Les Vieilles Charrues at Carhaix, and Rennes keeps an opera house and a national theatre going all year.

Cornwall's standout is the Minack Theatre, an open-air stage cut into the cliffs above Porthcurno. Beyond that, the county has male voice choirs, pub folk sessions, Padstow's May Day celebration and touring shows at Truro's Hall for Cornwall, but little regular classical music.

Brittany has a real spa tradition. Thalassotherapy began in Roscoff, and seawater spas line the seafronts from Quiberon to Perros-Guirec, so a calm spring or autumn stay can revolve around them.

Cornwall relies more on its slow pace than on treatments. There are spa hotels above Watergate Bay and Carbis Bay, and wood-fired beach saunas paired with cold sea swims. In summer, though, the crowds make it hard to unwind.