Tuol Sleng Genocide Museum

In 1975, Tuol Svay Prey High School was taken over by Pol Pot’s security forces and turned into a prison known as Security Prison 21 (S-21); it soon became the largest centre of detention and torture in the country. S-21 has been turned into the Tuol Sleng museum, which serves as a testament to the crimes of the Khmer Rouge.