Anse Source d'Argent is walled by granite older than almost anything you can stand beside — pink boulders that formed about 750 million years ago. These are the only mid-ocean islands built of granite rather than coral or lava, a stranded fragment of the supercontinent Gondwana whose improbable rock was once cited as early evidence that continents drift. Weathered by wind and rain into smooth, honey-and-rose curves, the boulders rise straight out of powder-white sand and split the shore into a chain of shallow natural pools. An offshore reef keeps the water calm, warm and glass-clear, glowing turquoise over the pale seabed. This one stretch of La Digue's west coast has become the emblem of the Seychelles — the backdrop of Bacardi rum commercials and countless other campaigns, and often called the most photographed beach in the world.
You reach it only one way: on foot or by bike through L'Union Estate, a former coconut-and-vanilla plantation. Past the gate the path passes an old copra mill, a colonial plantation house, and giant Aldabra tortoises that can weigh a quarter of a tonne, before opening onto the sand. What follows is not one beach but a string of small coves, each walled off by boulders the size of a room and linked by shallow, glass-warm water you can wade between. Snorkellers drift over the shallow flats among small fish, though the lagoon is calm rather than deep. And because the beach faces west, the granite ends each day glowing copper and rose as the sun drops behind the reef and the palm trees turn to black silhouettes.