As we're enjoying Chile so much we decided to change our initial plans to stay a bit longer in the country. We booked tickets to the coastal city of Iquique, about 7h on bus from San Pedro. Nice beach, lovely seafood, interesting architecture. We visited "Humberstone", which is a ghost town, built in the desert to extract nitrate of soda at the end of the XIXth century. Following the invention of synthetic fertilizers, production of Chilean "white gold" declined and the town was abandoned in 1960. Most of the buildings are still in place (school, market, hotel, theater, houses..). The site is protected by Unesco rules but you are allowed to wander around without any safeguard!