The hull of an old steamship is outlined by the vegetation that grows atop it in Mallows Bay. The bay in Charles County, Md., is the final resting place for more than 100 World War I-era cargo ships. It has been named a National Marine Sanctuary. (John Kelly/The Washington Post)

The newest National Marine Sanctuary in the United States wasn’t chosen for its natural beauty. It was chosen because of what Susan Langley calls the “dead ships.”

Langley is the underwater archaeologist for the state of Maryland’s historic preservation office. On a recent morning, I sat behind her in a two-person kayak — a “divorce kayak,” she called it — as we paddled around what’s known as the Ghost Fleet of Mallows Bay. Here rest the skeletal remains of more than 100 wooden steamships, hastily built for World War I before eventually winding up on the Potomac River in Charles County, Md.

There were about two dozen people in our flotilla. Many were interns at the National Oceanic and Atmospheric Administration, the agency that overseas the marine sanctuary program. The kayaks belonged to Atlantic Kayak, which organizes regular tours of the bay.

Langley brought her own paddle. She spends a lot of time on the water or in it.

“Those are her boats,” said Paul “Sammy” Orlando, a regional coordinator in NOAA’s Office of National Marine Sanctuaries, as we waited to slide down the kayak ramp and into the water.

“My babies,” Langley echoed.

The dead ships were dead almost from the moment they were launched. The war ended, and the ships were sold for salvage. Some wound up in Alexandria to be disassembled, their metal fittings removed and sold for scrap.

Then operations switched to Mallows Bay, about an hour’s drive south of Washington, and at Widewater, a bay across the river on the Virginia side. The ships were rafted together, sunk in place, then burned to the waterline.

In the depths of the Great Depression, Charles County, Md., got 15 percent of its income from wildcatters breaking the wrecks.

Many ships, however, were never fully disassembled. They rest here still, and at low tide, they emerge like bony limbs from a flooded graveyard.

Fascinating. And yet the first ghostly wreck we came to had nothing to do with that. It was the Accomac, a ferry that loomed over us as we paddled closer. The Accomac showed up suddenly in 1973, apparently abandoned by its owner.

“How do you sneak a vessel that size into a bay?” Langley said. “There’s already a bunch of wrecks. No one will notice one more.”

The Accomac is the most intact vessel at Mallows Bay, making it what lawyers call an “attractive nuisance.” Plans are underfoot to add signs warning against trying to board it, even if just looking at the rusty, jagged hulk makes you want to get a tetanus shot.

“I have to pretend I care about people, but I care about my resources,” Langley said. “Don’t walk on my ships.”

A lot of people down here hope the new sanctuary designation will boost tourism. At the boat ramp, you can pick up a paddler’s guide to Mallows Bay, printed on water-resistant paper so you consult it as you float over the wrecks.

We paddled north past the hull of the Benzonia, launched in the Columbia River in Washington state in 1919.

“The Benzonia was going to be our poster child,” Langley said.

The outline of the ship was once recognizable, the jagged wooden stern standing high above the water. Then a fire broke out, rendering it less picturesque.

The fire was mysterious, but Langley thinks she knows what probably happened: An osprey nest in the stern caught fire, ignited by sunlight through some prismatic plastic trash carried in by a messy osprey.

“You look at a bald eagle’s nest, and it’s very neat: The chicks are here, there’s some fish there,” Langley said. “An osprey nest looks like a frat house.”

We saw both: eagles and ospreys. Hummingbirds, too. And egrets and herons.

And V-22 Ospreys. Quantico Marine base is across the river, and the transports split the air like massive dragonflies.

Low tide is the best time to see the Ghost Fleet, but paddling can be hard then. The shallow waters are choked by hydrilla, an invasive seaweed. Even at high tide, when I was there, you get a sense of the post-apocalyptic oddness of the place, overwhelmed by the feeling that nature reclaims all.

“I always say, come for the World War I ships and stay for the rest,” Langley said.

Twitter: @johnkelly

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