Gulf of Morbihan Boat Tour

The Gulf of Morbihan is an almost landlocked inland sea in southern Brittany, covering roughly 100 square kilometres and scattered with more than forty islands — most of them privately owned or nature reserves. The name Morbihan means 'little sea' in Breton, and crossing its shimmering expanse on a guided boat tour, with megaliths, oyster beds, and ruined abbeys slipping past, is unlike any other day trip in the region. The main departure point is the Port de Vannes, five minutes on foot from Vannes train station, which is served by TER from Rennes in approximately one hour and thirty minutes with fares from €14. Navix (navix.fr) and Compagnie du Golfe (compagnie-du-golfe.fr) both operate tours from Vannes, with half-day circuits from approximately €22 per adult and full-day island-landing tours from €35. The full-day tours typically include a disembarkation stop on the Île-aux-Moines — the gulf's largest island, with a village and lanes to explore — and sometimes on the Île d'Arz, giving passengers one to two hours ashore before the return circuit. The gulf's waters move rapidly through its narrow entrance near Port-Navalo, and the tidal interaction with the sheltered basin creates an environment supporting grey seals, migratory wading birds, and the extensive oyster and mussel farms visible from the boat. The prehistoric menhirs of Locmariaquer and the Er-Lannic stone circles, partially submerged by millennia of rising sea levels, are visible from the water, connecting the tour to Brittany's extraordinary megalithic heritage. Vannes itself adds a satisfying bookend: the walled medieval city around the Cathédrale Saint-Pierre is compact and well-preserved, with half-timbered houses and the thirteenth-century covered market hall, the Cohue. Morning arrivals from Rennes can spend an hour in the old town before the late-morning boat departure, and return trains to Rennes run until around 20:00.