This former saltpeter refinery is located in the Atacama Desert, 40 km east of Iquique. It was named after James Humberstone, a British chemical engineer who emigrated to South America in 1875. He made his fortune from saltpeter, which was dug out of caliche – the nitrate-rich crust of the desert – and used to make fertilizer. For a while in the late 19th and early 20th centuries, almost all the saltpeter in the world came from the Atacama Desert. It was known as white gold and was in huge demand in the industrializing countries of Europe. Why? Because they needed fertilizer to help grow food for their rapidly expanding populations.
Up to 3700 people used to work and live in this town at the peak of activity in the 30’s. The works closed in 1960. In 1970, it was declared National Monument and opened to tourism. In 2005 it became a World Heritage Site by UNESCO.