Chacabuco Saltpeter Office
Built between 1922 and 1924, on the site of the old Lastenia Salpeter Office, it was functional until 1940. It was very large, with a high production capacity and excellent living quarters. It used to produce 150 million tons of saltpeter and 922.000 kg of iodine annually.
During the military dictatorship was expropiated and used as a prisoners field that became in one of the biggest of Chile. Nowadays, the installations are not in a very good state because the machinery has been dismantled, but the houses are still preserved. It was declared a National Historical Monument on July 26 1971 with the aim of safeguarding the evidence of what was the development of the saltpeter industry in Chile.