Pretty much a MUST on any South America backpacking itinerary are the Bolivian Salt Flats! But getting there is an adventure in itself - namely a 3-day 4x4 tour through deserts, along frozen lakes and up to the geysers at ~ 4,900m/16,000ft altitude. It includes a night in a hostel made out of salt, flamingos & alpacas and the train graveyard in Uyuni.
We started our tour in San Pedro de Atacama in Northern Chile.
First stop: the Bolivian Embassy - which was a small brick building with a Bolivian flag in front of it in the middle of nowhere. Once we got our passports stamped we were off to explore some pretty crazy environments for the next couple of days.
It's incredible to witness how the landscapes & climates change: you start in flat desert terrain surrounded by mountains, then you climb up to check out the geysers and then down again past pristine lakes and before you know it you're surrounded by cactus plants and you'll get the first glimpse of the salt flats.
Needless to say, that we were completely off the grid during this trip - no cell connection and no WiFi. Granted, that was in 2010 - so things may have changed now. Or they haven't - in which case you'll be forced to give your full attention to the breathtaking scenery you'll find yourself in ;)
Get carried away!