Bel Hôtel Oléron Thalasso & Spa, MGallery, opens on Gatseau beach: 102 rooms, 27 Phytomer cabins and Pierre Gagnaire’s table

In the south of the island of Oléron, where the Saint-Trojan national forest meets Gatseau beach, the site’s former thalassotherapy centre has been completely redesigned. Bel Hôtel Oléron Thalasso & Spa opened at the beginning of summer under the MGallery Collection banner, Accor’s boutique hotel brand, and was inaugurated on 17 September 2026. It is the island’s first five-star address, and one of the few thalassotherapy centres on the Atlantic coast backed by a chef of Pierre Gagnaire’s stature.

102 rooms between pines and ocean

The hotel has 102 rooms, including eight suites named after local places, such as “La Lumineuse” or “La Domaniale”. All have a balcony or terrace, facing the pine forest or the bay. The decor features weathered wood, mineral tones and the island’s sands; the bar menu, with its “Cocktail Dune”, blends marine notes and pine resin. The “M Moment”, a ritual unique to each MGallery, takes the form here of a picnic for two on the beach at sunset.

A 27-cabin Phytomer thalassotherapy centre

The heart of the address remains the sea. The thalassotherapy centre, entrusted to the Breton brand Phytomer, features 27 treatment cabins, a heated seawater pool with hydromassage jets overlooked by a mezzanine, a hammam, a jacuzzi, a glazed sauna, a Scandinavian bucket and a solarium facing the ocean, with a tea room and a gym. The programmes include the classics of the genre, hydromassage baths, seaweed wraps and massages, and extend outdoors: yoga, breathing and paddleboarding on the bay.

Pierre Gagnaire in the dune kitchen

The restaurant OYAT, subtitled “Cuisine des Dunes”, bears the signature of Pierre Gagnaire, with a dining room open to the ocean, beach service and a Chef’s Table for 12 to 16 guests. The chef, present in Paris, London or Tokyo, adds a seaside address to his French portfolio with Oléron.

What this changes for Oléron

The island, long reserved for campsites and rentals, gains a hotel capable of retaining a clientele out of season, with the thalassotherapy centre operating all year round. MGallery, which has more than 127 addresses worldwide, sees it as another French “sanctuary” following its recent openings, such as Ink 48 which became the brand’s flagship in New York. To compare with other spas on the coast, our guide to spa hotels in Brittany covers the neighbouring coastline.

Photos: © Accor · MGallery Collection · Bel Hôtel Oléron.