To paddle safely in the waters of Mallows Bay, where a ghost fleet of ships have long been decaying into the Potomac River near Nanjemoy, MD, it is best to view it as one big navigational hazard. I brought my Kevlar kayak for my maiden visit on Nov. 18, a placid chilly day, and my newly gel-coated beauty emerged unscathed. Next time, though, I’ll bring a heavy-duty plastic kayak just to be safe.

The issue is all the rusty metal poking up out of the water. About the only remains left of the many decayed ships littering the river bottom here are the large rusty fasteners that used to hold them together. Many are pretty visible today, jutting up out of the water’s surface. But many more are submerged, poised to impale or gouge a passing vessel’s hull.

Turns out, you’re supposed to kayak around the fleet, not through their watery graveyard, as I did. It’s all there in the handy map and guide that I neglected to pick up at the visitor’s shed and peruse before embarking: the whole area inside the 2.5-mile self-guided loop is shaded and labeled with a “warning” symbol. “Dangerous metal objects lie below the surface of the water,” the guide explains, “may not be visible.”

So on the first outing I broke the rules. I’d never have done it if the day had been windy and the waters rough. In the calm, though, water-borne photography was possible, so now I have a whole slew of images of what’s left of the burned-out fleet of World War I-era wooden steamships, and the uniquely protected ecology their presence has created at Mallows Bay, creating opportunities for flora, fauna, and errant paddlers.