Our journey to the highest desert in the world begins in Potos�, in southwestern Bolivia. At 12,000 feet above sea level, it is the highest city in the world. The indigenous people of this high cold desert have used llama trains for thousands of years to transport the salt harvested in the area's dry lakebeds. Our explorers also visit the Salar de Uyuni; at over 4,000 square miles it is the largest salt lake in the world. Here, traditional methods of salt cutting continue the same way as they have for centuries. Cutters build tiny igloo-like huts out of salt blocks and remain at the site for 5 days. Along the shores of the Salar, the desert is profoundly evident as the majestic groves of thick tall pasacana (similar in stature to the Saguaro cactus) grow on the surrounding frozen hillsides.