It’s a bright cold day in the austral midwinter. The low sun is dropping into the lake, drawing long shadows from the dead trees, broken streetlights, and bent telephone poles that stick out of the water as if planted there. Three flamingos are floating down the Avenida De Mayo, past the half-sunken ruins of the Azul Hotel. Their pinkness almost glows against the dry white crust that covers every exposed surface. It looks like ash, or frost, but is actually salt. There is 10 times more salt in this water, per cubic centimetre, than in any of the world’s oceans. The lake was named “Epecuen” by the Mapuche tribes who once populated the surrounding lowlands of central Argentina – it was their word for the itch caused by the salt drying on their skin, though they also found that it had health-giving properties.