Uyuni salt lake has the most beautiful diversity of landscapes I've ever seen.

12000km2 of salt, desert, lagoons full of flamingos, active volcanos, cactus, sand and all sorts of strange animals.
We did a 3 days tour, with the 4 wheels drive we covered more than 1000km in 2 days on sand and salt (like a small Paris-Dakar), slept in salt hotels with no heating system and a night temperature of -20C...Brrr...freezing..., had a bath in natural hot springs, and saw smoking volcano.
Incredible beauty!!