The area was just incredible--the port of La Rochelle along with this other hidden cove of Meschers-sur-Gironde with troglodyte dwellings pounded by the surf into the cliff was like a pirate theme-park. The caves there actually saw some piratery and were once host to French protestants who had to practice their religion in secret.
A sort of regional mascot too was a donkey in pajama bottoms, and later I learned that these pants were worn to protect them from mosquitos while working in the salt-flats that brought these cities great prominience.
The mud-flats that are part of the oyster culture and the salt-flats which gave Aquitaine a monopoly are nourished by sediment washing in from the mouth of the Gironde colliding with the silt of the ocean. Eventually, and probably rather sooner than anyone expected, the sediment choked this fortress off from the port by a good ten kilometers.
Not useful for fending off invading ships, the town--which was also the birthplace of promogenitor Canadien Samuel de Champlain, the fort and billeting has been well-preserved. There was a lot of neat stuff going on here and I have a lot of homework to do.