We got up in Potosi and headed over to the main square, which was really pretty and surrounded by nice churches and buildings like the theatre. We then went over to the Casa de la Moneda of Potosi, which used to be the mint and was a really interesting tour. The guide showed us around firstly some 17th century paintings held in there then took us through the old process of making coins there. Because Potosi is founded on a massive hill that has been a silver mine for the last 500 years (although they mostly mine zinc now) it became one of the centres of the Spanish empire for minting coins.

He showed us through the processes as it changed with time, as much of the old machinery had just been left there, preserved by the cool dry climate up the mountain (Potosi is the highest city above sea level in the world, c. 3000m).

After the tour had finished we got some lunch then wandered around the centre for a time. Due to the silver production it used to be very rich and there were loads of old colonial buildings.

Early afternoon we then went out on a tour of the mines. It was interesting to see the appalling conditions the miners still work in (albeit for much more money than any other job), the dust in particular really got to my throat and causes cancer. Apparently the average miner lives to 45-55.

It was a dismal, dangerous place with one set of tracks along the path that heavy iron carts hurtle along, carrying 3 tonnes of minerals. Each time a cart came against another the empty one was hurled to the side (usually where we were standing waiting) to let the full one pass out. They were willing to let tourists in but only if we brought presents like coca leaves, sweet drinks and dynamite, and didn't get in the way - the carts didn't stop for us so we had to really run between them.

We spent a couple of hours in the mines, climbing up and down trying not to fall or be hit by the carts. It wasn't fun but was worth seeing.

After the tour finished we went for pizza with some of the people we met on the tour, which was really nice.