Humberstone and Santa Laura Saltpeter Works are two former saltpeter refineries located in northern Chile. They were declared a UNESCO World Heritage Site in 2005, as a testament to the historical importance of saltpeter mining in Chile and the culture and social agenda that developed around it in the late 19th century. The works were placed on the World Heritage List in Danger that same year, due to the fragility of the derelict buildings, but was removed in 2019.