There are two other forts in the neighborhood. Fort St. Philip is on the river’s east bank, but as it’s privately owned and accessible only by boat or helicopter, it’s a bit hard to visit. Likewise, the circa 1700 site of Fort De La Boulaye — built by early French explorers and now situated on Highway 39, not far from New Orleans — is on private property, and there isn’t much left to see despite its importance to Louisiana’s first European settlers.

Plaquemines is an enchanted place, beloved by nature lovers and sportsmen alike, but given its fragility, how long it will remain a place at all — in the sense of a location that signifies firm land — is anyone’s guess. Even so, from its earliest days as a European foothold on the new continent, and on through hurricanes, wars, epidemics and social and economic upheavals, the region hung on. Then the 1927 Mississippi River flood came along, and when the powers-that-be in New Orleans realized that the flood would most likely inundate the entire city unless drastic steps were taken, they dynamited the levee some 13 miles below the city, sparing the Big Easy by funneling the floodwaters into Plaquemines, and, in the process, devastating it. Randy Newman recounted the disaster in his song “Louisiana,” which goes, in part: “The river rose all day, the river rose all night / Some people got lost in the flood / Some people got away all right.”

What Mr. Newman doesn’t sing about is how, in the aftermath of the flood, the Army Corps of Engineers was authorized to do what it had to do to prevent future catastrophes, the upshot being that it changed the course of nature, which in turn set in motion a cycle of increasingly more ruinous storms, followed by increasingly more expensive, if unavoidably temporary, fixes.