Security Prison 21 a.k.a S21 once belonged to Khmer Rouge is now open to the public as The Toul Sleng Genocide Museum. They say only 8 survived among 14,000-20,000 prisoners who were imprisoned from 1975 through 1979. I can't believe this happened in the time after I was born. The site was originally built as a lycée, and ironically, a facility to nurture humanity was turned into a place to destroy humanity.