Playa Flamenco is a kilometre and a half of white sand wrapped round a bay on Culebra, off the east coast of Puerto Rico. There is nothing behind it but low green hills. The bay shelves so gradually that you can wade a long way out and still be standing, with nothing underfoot but fine pale sand. Walked early, before the day boats land, the whole arc is yours. At either end the sand gives way to volcanic rock, and the shallow reef there gathers parrotfish and the occasional ray, with sergeant majors shoaling tight against the rock, close enough to reach from the beach. The runway on Culebra takes nothing bigger than a light propeller plane, so the hop from San Juan flies low for half an hour. You watch the reef system lay itself out under your window: pale shallows, dark coral heads, then deep blue where the shelf ends.
Two rusted hulks sit half-sunk in the sand where the beach runs out to the west, close enough to the water that the surf washes round their tracks. They are Sherman tanks, and they did not break down here. The Marines towed them onto the sand so the ships and aircraft working this range would have something to shoot at. The firing stopped because the islanders stopped it. In 1970 the people of Culebra began walking onto the range itself, and for seven months they held marches, sit-ins and blockades on the target area so the exercises could not run. The Navy agreed to go, and was gone by 1975. The headland at the end of the beach is still closed, and thirty to forty thousand pairs of sooty terns nest on it, filling the sky over the point until the broods go to sea in September. Leatherbacks come up this shore to nest between April and June, and each nest is staked where it is found. The tanks get repainted constantly — slogans, cartoons, initials, whatever somebody brought a tin for. The one you photograph will not be the one in anybody else's picture from last year.