Stevo and I had collected two travel buddies in our last couple of days in Sucre, in the form of Tessa and Nicki, two medics at Bristol. We decided to share a cab together down to Potosi. This was a 2 1/2 hour journey and cost a grand total of twenty quid, so a fiver each. I love Bolivia.

Once in Potosi, we found our way to the Koala Den which had been recommended to us by a few people. We checked in and were shown to our dorm, which was right at the top of the building. I need to put into perspective exactly what this means - Potosi is the highest city in the world, at an altitude of around 4,100m above seal level. Walking in the street is a struggle here because the oxygen concentration is so low. Going up four floors of steps left me feeling like I had just played 90 minutes of Premier League football. Exhausted.

Once we´d settled our stuff in we booked onto a mine tour for the next day through the hostel. We then hit the streets to scout out the town. We checked out the local markets for a few hours and then hit a restaurant that had been recommended by the guide books. We got a relatively early night in preparation for the tour the next day.

We were picked up in the morning and first taken to a depot where we were introduced to our guide and given all our gear. This included big baggy trousers, big baggy jacket and big miners hat with headlamp. At one point, our guide (there were several guides as we were split into small groups) came out in just a things and miner´s hat. It was quite disturbing. All looking like Bolivian miners, we headed to the miners´ market where it is tradition to buy gifts for the miners. We clubbed together and bought several bottles of soft drink (which they apparently love), coca leaves and most interestingly, dynamite. The stuff is totally unregulated in the city. You can buy dynamite like sweets in a shop. Nuts.

Our next stop was the processing plant, where we saw what happens with the end product from the mine. We then went into the mine itself. We first went to see the mine Tio. This is a statue of the Devil, to which the miners make offerings and sacrifices in the hope that the Tio doesn´t punish them by causing an accident or a collapse. This tradition came about from the times the Spanish ruled - they had made the conditions so terrible for the indigenous people working in the mines that the locals refused to continue. The Spanish made up a cock-and-bull story about how there is a mine god who would punish them if they didn´t work (the Spanish word for God is Dios, but in Quechua there is no letter D and so the locals started using Tios, which later became Tio). Getting to the Tio was difficult. We crawled through a small tunnel, with rocks all over the place battering our knees and elbows as we did so. The Tio was surrounded by previous offerings.

Next, we headed to a spot where a young miner was working. To get here was even worse. We had to climb down (awkwardly) into a small space before going into a tunnel one-by-one, crawling. Nicki had to wait in a tiny dead end while the guide explained what the young worker did. It was a really grim place. I was dark except for his headlamp, he was often alone (sometimes accompanies by his father and brother) and he could never do anything but crouch on his knees to do his work, which was physically taxing. It was shocking to hear that at just 18, he had been working in the mines for four years already. His job all day, every day was to make holes in the rock face into which dynamite would be inserted and detonated. He spent twelve hours a day doing this with no equipment other than a chisel and hammer. Truly shocking.

After this, we made our way to one of the larger parts of the mine, where we could walk (albeit hunched over a little). This was where the mineral rocks were put into the huge wagons and transported to the surface. We watched as some of the miners placed dynamite under a large rock to blow it into smaller pieces. We were instructed to run by the guide, who told us we had three minutes before the fuse blew. It blew after a minute. It caught us all off guard and everyone jumped with the explosion. As we made our way out of the mine, the guide shouted for us to turn around and find a space in the walls to take cover from an oncoming wagon. These things weighed a ton and if it hit you, you were as good as dead. We all found somewhere just in time to see the wagon shoot past. It really brought home the fact that we were in a working mine.

After two hours of crawling and walking in the dusty, hot, claustrophobic mine, we left and were all relieved to see daylight. It was such an interesting experience but I cam out never wanting to go back into a place like that again. That was after two hours. Those guys do it day-in-day-out for twelve hours.

We spent the rest of the day cleaning ourselves up and heading to the markets to buy ingredients for a spaghetti bolognese. We also picked up a few bottles of much needed wine after the intense experience of the day. The following morning the four of us were set to grab a bus to Uyuni.