S-21 Prison, also known as Tuol Sleng, was set up by the Khmer Rouge in a former school building in the center of Phnom Penh, as one of an estimated 150 to 200 detention centers in the country.

This Security Prison was used to detain, interrogate and torture suspected  enemies of the Pol Pot regime into confessing to alleged crimes.

From here, prisoner sentenced to death were transported to a plot of land known as the the Killing Field, located some 15 kilometers from town, to be executed and buried in shallow graves (fig.).

Between 1976 and 1979, an estimated 20,000 people were imprisoned at Tuol Sleng, of which the name translates as ‘Poison Nut Hill’, after a tree with the botanical name Strychnos nux-vomica.

Today, the former prison is a Genocide Memorial and Museum, that aspires to preserve the evidence of the atrocities at the hands of this brutal communist regime.

Besides the preserved interrogation rooms and torture tools, shackles and cells, the Genocide Museum displays mugshots of prisoners, which were taken upon their arrival at S-21, and also features a memorial with the names of victims.