Humberstone and Samta Laura Saltpeter Works were inscribed as UNESCO World Heritage in 2005 and immediatelely put on the list of world heritage in danger (until 2019) to get funds for preserving and stabilizing the remaining buildings.
There had been extensive damage partly due to earthquakes but also because of looting. The harsh desert climate in combination with wind and coastal fog (camanchaca) had left most surfaces covered with a mixture of sand and salt, corroding the metal parts.

whc.unesco.org/en/list/1178