KASKASKIA, Ill. » When Manny and Dorothy Brown stand atop the stairs rising to their screen door, they look at the overgrown field across Grand Avenue and still see Kaskaskia’s buzzing general store. Fathers are planning turkey shoots; mothers, bake sales. Schwinns clatter past rows of homes while little cowboys and Indians shriek down by the church.

That Kaskaskia is all almost gone now, washed away over the years by two huge Mississippi River floods and then residents’ growing suspicion that their quirky and once vibrant town — the first capital of Illinois — was vanishing into U.S. history, like wild buffalo or penny postcards. If this country has an Atlantis, it is Kaskaskia, Ill.

"I’m not coming back if there’s another flood," said Dorothy Brown, 80, one of only 14 full-time residents left in the three-by-five-block area that makes up Kaskaskia proper. "I’m too old to clean up that kind of a mess again."

Fifty other stalwarts still live on the wider expanse of Kaskaskia Island, about 60 miles south of St. Louis and originally not an island at all. French missionaries settled in 1703 on what was then a peninsula in southwestern Illinois territory, with the Mississippi River (and what is now Missouri) on one side and the Kaskaskia River on the other. The outpost preceded St. Louis as the West’s primary economic center. It was given a mammoth bronze church bell from King Louis XV — 11 years before a different one, in Philadelphia, became the Liberty Bell — and went from French to British to American rule before 1818, when it became the bustling 8,000-resident capital of the new state of Illinois. The capital later moved north to Vandalia and ultimately to Springfield.

Floods came and went, but the Mississippi really meant business around the Civil War after upstream steamboats had sheared its shores for firewood, weakening its banks. The river began to creep east across the peninsula’s width until, on the night of April 18, 1881, it finally met and slowly overtook the channel on the other side. Kaskaskians moved their church, their cherished bell and a few other buildings brick by brick 2 miles inland before the original town began slipping slowly under the relocated river.

Suddenly an island cut off from mainland Illinois, the new Kaskaskia has asked residents ever since to put up with some weirdness. No connection was ever built across the new Mississippi, leaving its only access a bridge from Missouri. So getting to this Illinois town requires a 20-minute detour through the neighboring state. Still very much Illinois residents, Kaskaskians eventually lost postal service and now must receive mail at addresses in St. Mary, Mo., causing tax problems galore and more than a few tiffs at the Illinois Department of Motor Vehicles.

"Other people think it’s strange, but those of us who have spent our lives here have never had it any other way," said Emily Lyons, a lifelong resident and the town’s de facto historian.

Losing residents with every passing decade, Kaskaskia had remained large enough to house three schools and about 600 residents when a 1973 flood drowned homes in 13 feet of Mississippi muck. The 200 people who returned and rebuilt were hit with an even more devastating flood in 1993, when 20 feet of water destroyed most homes and the resolve of all but the staunchest loyalists.

Today the church that was moved in the late 19th century is still in use, with bricks on the second floor showing some discoloration where floodwaters rose in 1993. (Mass is on Saturdays because no priest can get there on Sundays.) Louis XV’s old bell — cracked, just like Philadelphia’s — still hangs in a nearby shrine, metaphorically ringing out Kaskaskia’s three centuries of history and fortitude.

"People say nothing’s down there. But a lot’s been here; you just can’t see it anymore," said Mary Brown, who along with Lyons has spent countless hours restoring historic buildings on the island. "We’ve been handed this baton. Hopefully, the younger ones will have the dedication."

There are not many younger ones left, alas. With the closest school 20 miles away in Chester, Ill., requiring clunky trips down and through Missouri just to get there, the island has only a few children to inherit their parents’ and grandparents’ strong ties. Even the mayor is trying to move his family but has not been able to sell his house.

Herbert Klein, a lifelong resident who still farms 330 acres of soybeans on the northern end of the island, where parts of the original town once stood, chuckled and said that floods in 1973 and 1993 did not bode so well for 2013. One family rebuilt a small home on Third Street just this year — this time, perching it on steel stilts 16 feet above ground level — but Klein said that many folks now preferred mobile homes that could be whisked off the island quickly.

"If we have another flood," he said of Kaskaskia, "it’s done for."

Dorothy and Manny Brown, residents since the Depression, figure that floods are more part of their past than their future. Standing on that top step, their eyes below the level of the 1993 flood, they remember what the Mississippi can and probably will someday do. Yet while outsiders look at Kaskaskia and see only water, all they see is home.