A sombre reminder and testimony to the brutality of the Khmer Empire, the killing fields of Choeung Ek exude a sense of sadness and great loss. The place is a reminder of the huge demise of citizens the nation faced under the rule of Pol Pot; a time when many Cambodians died of hunger and disease while a majority were murdered, including the nation's most intellectual, such as doctors and teachers, suspected of opposing the Khmer rule. Over 17,000 people are believed to have met with death in Choeung Ek home to 129 mass graves. There the memorial stupa harbouring over 8,000 skulls is a stark reminder while the Tuol Sleng Museum which you can explore, was once a school transformed to a Khmer owned high-security prison, still exudes dark undertones.