During the French colonial period, Côn Đảo had around 18 hard-labor stations, but only a few remain today—such as the Lime Kiln Station (Sở Lò Vôi), the Salt Factory (Sở Muối), and the Plantation Station (Sở Rẫy). These are among the 46 official historical sites on the island.
The Salt Factory was located in An Hội village, responsible for producing salt for the entire island. It was also one of the places where large numbers of lưu án prisoners were held—sometimes up to 600 people at a time.
This was where prisoners were forced into harsh labor, making salt under extreme conditions in the salt fields of An Hải village. During the August 1970 uprising, prisoners on Côn Đảo organized a coordinated resistance movement. At the Salt Factory, disabled and severely ill prisoners directly raised demands against the inhumane “dry rations” policy, requesting fresh vegetables every three days and the issuance of clothing.
After three days of being ignored, the prisoners dragged themselves out onto the road, raised banners, and shouted slogans in protest. Colonial forces violently repressed the demonstration, injuring 15 prisoners.
