During the rainy season (November to March) the water accumulates on the surface of the Salar de Uyuni and creates a giant mirror that perfectly reflects the sky and clouds above and you can play with the optical illusions the lack of horizon causes. With nothing in sight for miles, taking "perspective pics" is a popular pastime for tourists and photographers.
During sunrise and sunset, the colours reflected off this huge mirror are truly spectacular.
Stargazing inside the Uyuni Salt Flat is amazing, but with the water reflecting the perfect star-filled sky, it is a whole new experience.