Make a splash on a shimmering shore, Hérault’s impressive Etang de Thau is a lagoon unlike any other

There’s a kaleidoscope of life and cultures around the Etang de Thau. About 21km long and 8km wide, this shimmering stretch of water is one of the largest lagoons on the Mediterranean shores. The area is variously a haven of great seafood, safe adventure, serious health treatments, charming villages and wonderfully colourful traditions. Of course, given that this is the Languedoc region, there are plenty of very productive vineyards, too.

At the western end of the lagoon, you can literally get a taste of the area, for here you can visit an oyster farm and also sample the famous Noilly Prat vermouth.

Just outside the sleepy village of Marseillan, Stéphane Saez runs La Grande Bleue oyster farm – which you approach through vineyards that seem to be planted into the lagoon itself. Stéphane explains to visitors that because the Canal du Midi empties into the lagoon nearby, there is a special quality of part-fresh, part-salty water that is richly beneficial for growing oysters. These are complex creatures to farm: they are grown on strings; they change sex every year; and the water quality is tightly controlled in order to meet the strict requirements of the renowned AOC Bouzigues label, under which oysters in this area are marketed. The absorbing afternoon tour culminates with a tasting, accompanied by a glass of the local Picpoul de Pinet white wine, which is a particularly good match with seafood.

By the lovely old harbour of Marseillan you’ll learn how the lagoon environment is also integral to Noilly Prat, which has been produced here for more than 160 years. The vermouth is made with two types of white wine that are matured indoors for eight months and then left in barrels outside for a year, exposed to the wind, sun and salty air. Subsequently, the wines are blended and infused with herbs, the combination of which remains secret. A tour through this attractive old winery ends with a tasting of the original clear aperitif – the slightly sweeter red vermouth or amber Noilly Prat that is available only from the Marseillan headquarters.

For a complete change of pace, head to the beaches. The Marseillan Plage resort is several kilometres south. Stretching east beyond it lies the narrow bank of the lagoon, which is fringed with more sandy shores.

At the far eastern end the lively little town of Sète is set at the foot of Mont St Clair. It was purpose-built as a port in the 17th century, and its elegant town buildings are laid out along a series of canals – so you may feel as if you’ve reached a French version of Venice here. Wander the canals of the centre to take in the bustling atmosphere of the water traffic and to see fishing boats coming and going, trailed by seagulls. Take a cruise around town or into the lagoon then, for an extensive panorama, make your way to the top of Mont St Clair (it’s a short drive or a steep walk up more than 400 steps from the heart of town). From this vantage point you variously gaze over the sea, the terracotta roofs of town and the oyster farms of the lagoon.

Sète is an engaging world unto itself. About one third of the residents are descendants of Italian settlers (from Naples, in fact, rather than Venice) and this is reflected in the cuisine: try a tielle, a sort of pasta pie with a picquant squid-and-tomato filling, or macaronade, which is a local version of pasta with meatballs.

This spirited town is also renowned for the tradition of water jousting – a striking spectacle and a serious sport in which contestants attempt to knock each other off long platforms extending from boats. Tournaments take place in the summer on the Canal Royal. Indeed, there’s a party atmosphere during much of the summer, with a number of festivals held around town – among them are celebrations of photography in May; French song in June; jazz in July; and world music in August.

By contrast, a few kilometres north of Sète you reach the spa town of Balaruc–les-Bains. It was the Romans who first started using the warm thermal springs here for the curative treatments and therapeutic sessions, and today the town is the third largest spa resort in France. The mineral mud treatments here are said to be particularly effective against rheumatism and arthritis. The town also offers plenty of activities, from tennis to sailing, beach volley ball and pétanque. Meanwhile, visit the picturesque adjoining village of Balaruc-le-Vieux, an ancient medieval settlement that still retains its circular defensive walls.

Just west, there’s a happy mix of inland nature, seaside sport and historic charm around the market town of Frontignan. Set on the Peyrade and Ingril lagoons, which adjoin the Etang de Thau by way of the Canal du Rhône à Sète, Frontignan in many respects offers the best of all worlds. Its medieval heart centres on a lovely 12th-century church while its lagoon shores present 7km of golden beaches. There are four well-equipped campsites here and a bustling marina. Meanwhile, on the other side of the waters stretch the tranquil parkland and vineyards of the Gardiole hills.

Travel essentials Bay to remember

What to do and see
La Grande Bleue Oyster and Mussel Farm, Mas 778, Lieu-dit la Fadeze, 34340 Marseillan (00 33 4 67 53 14 91; conchyliculture.com). Guided visits around the farm are available on Tuesdays and Thursdays at 4pm, €6 including a tasting of mussels and oysters and a glass of white wine.

Noilly Prat, 1 Rue Noilly, 34340 Marseillan (00 33 4 67 77 75 19; noillyprat.com). Guided visits March to November daily between 10am-11am and 2.30-4.30pm (and until 7pm in the summer); adults €3.50.

Cruises are available around Sète and the lagoon with Circuit Canaux et Etangs (00 33 4 67 74 35 30) and Sète Croisières (00 33 4 67 46 00 46; sete-croisieres.com), which has boats with viewing galleries below the surface.

More information on the area can be found at the tourist offices at Marseillan Plage (00 33 4 67 21 82 43; marseillan.com), Sète (00 33 4 99 04 71 71; tourisme-sete.com), Frontignan (00 33 4 67 18 31.60; tourisme-frontignan.com) and Balaruc-les-Bains (00 33 4 67 46 81 46; balaruc- les-bains.com).

Where to eat
Le Poisson Rouge, 32 Rue Paul Riquet, 34110 Frontignan (00 33 4 99 04 05 53; lepoissonrouge34.fr). The menu of this bright new restaurant emphasises seafood, but other local fare, such as roast lamb, is excellent too. The setting, right on the seafront, is stunning.

Terre et Mer, 28 promenade JB Marty, Place du Cap St Louis, 34200 Sète (00 33 4 67 74 49 43; restaurant-terreetmer.com). An intimate and good-value restaurant serving beautifully presented cuisine based on local ingredients.

Where to stay
Port Rive Gauche, Rue des Pêcheurs, Marseillan Port, 34340 Marseillan (00 33 4 67 11 87 15; garrigaeresorts.com). A chic apart-hotel with a sleek spa. The 11 apartments have terraces with great views. Doubles from €175 without breakfast.

Grand Hôtel Sète, 17 Quai de Tassigny, 34200 Sète (00 33 4 67 74 71 77; legrandhotelsete.com). This elegant Belle Époque building in the heart of town has 43 comfortable rooms. Doubles from €75 breakfast not included.

Hôtel Mercure Sète-Balaruc-les-Bains, Ave des Hespérides, 34540 Balaruc-les-Bains (00 33 4 67 51 79 79; mercure.com). Newly renovated, this 86-room hotel has a swimming pool and courtyard restaurant and is close to the new O’balia spa. Doubles from €70 without breakfast.