The Salar de Uyuni, at an altitude of between 4,000 - 5,000 metres, is one of the largest natural salt lakes in the world and the contrast of the brilliant white and the vivid blue sky is extraordinary. Travel by 4WD vehicle along the shore of the lakes and lagoons, where encrusted crystallised salt and gypsum contrast with the red algae-rich saline water on which the vibrant James flamingos feed and breed. Curiously Uyuni is also the end of the road for the steam train enthusiast, for here in the desert is the 'train cemetery', a collection of locomotives and carriages rusting in the sun. A trip across the Salar de Uyuni is one of the highlights of a visit to Bolivia.