Saint Nazaire is always worth a visit to see the U boat pens. Noirmoutier island is connected by a bridge and also a 4.5 km long causeway which floods twice a day. Worth a look. If you take the small coastal lanes up to St. Nazaire there are several fortifications remaining from WW2, including Le Grand Blockhaus at Batz-sur-Mer, a huge bunker on five levels. The medieval city of Guerande is nottoo far away and Nantes is a lovely city with it's Château des ducs de Bretagne and Les Machines de l'île are spectacular.
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