During the 19th century narrow-gauge railways shipped minerals and nitrates through Iquique. Mining barons built opulent mansions, piped in water from the distant cordillera and imported topsoil for lavish gardens. Downtown Iquique reflects this 19th-century nitrate boom; the corroding shells of nearby ghost towns such as Humberstone and Santa Laura whisper of the source of this wealth.
Even when Iquique was reveling in its newfound riches, though, all was not well. The city witnessed one of the bloodiest events in Chilean labor history. In 1907, nearly 8500 strikers gathered around the Escuela Santa María to protest unfair treatment in the salitreras (nitrate mines). In exasperation, police and military fired upon the unarmed strikers, killing hundreds and wounding many more. Chilean folk group Quilapayún immortalized the tragic incident with their recording Cantata Popular Santa María de Iquique.
After the nitrate bust, Iquique reinvented itself primarily as a fishing port, shipping more fish meal than any other port in the world. However, it was the establishment of the zona franca in 1975 that made this one of Chile's most prosperous cities.
The city’s history has been defined by economic cycles. The first of these was the guano extraction period. After this came the mining of silver, first worked by the Spaniards in 1542. Then, in 1830, the first shipment of nitrates to a foreign destination was made, marking the start of the period which would raise the city to the pinnacle of fortune.
When the last nitrates plant, Victoria, was closed, the end of that magnificent period was greeted with sadness, but it was replaced by fish, which is a rich resource along the coast. This occurred around 1960.
All the economic development which has occurred in the city has brought with it the construction of beautiful houses and buildings for various purposes. The occurrence of two earthquakes and tidal waves in 1868 and 1877 destroyed virtually all of these.
Then, under Chilean administration, the cove of Iquique became a port, and a busy, feverish, cosmopolitan city. Thus by 1925 there was a wealth of construction of new houses and other buildings for public services, such as the horseracing course and the bicycle track.
Today, the latest economic cycles to bring life and wealth are copper, the Freezone (business) and tourism. What remains of the past are the memories represented by the National Monuments and other important buildings which are still preserved.