Shot on the Salar de Uyuni (Salt Flats) in Bolivia. It's kind of eerie how the disused rail tracks start at the salt flats and just disappear in to the distance.
Originally built by the British in the late 19th century, the railway was used to carry minerals to the Pacific coast. At more than 3,500 metres (12,000') the climate there is harsh, often windy and nearly always cold. The thin air plays havoc with your body and it's hard to imagine what it must have been like working on a project like this in the 1800's. It's said that the local Aymara population were less than impressed with the efforts and frequently sabatoged the work and subsequently the trains themselves.
The train graveyard, which is close by, has dozens of rusting engines and rolling stock. The whole place is like an interactive museum of engineering. I'll post some images of those up too.