The brand-new bus gleamed as it weaved through rush-hour traffic in Cambodia’s capital. It was headed to a school, bearing a lesson about the country’s darkest period.

About two-thirds of Cambodia’s population is under 30, born a generation or more after the genocidal rule of the Khmer Rouge in the late 1970s. Many of those young people have only a general awareness of its atrocities, which left at least 1.7 million Cambodians dead.

That horrific history has been thoroughly documented, in court documents and at places like the Tuol Sleng Genocide Museum and the killing field in Choeung Ek. But both of these are in the capital, Phnom Penh, and most Cambodians live in the countryside.

The bus’s mission is to bring the history to them. An international effort, it is outfitted with touch screens, laptops and projectors and connected to a vast digital record of the Khmer Rouge’s crimes against humanity, including executions, enslavement, torture, starvation and forced separations.

Its destination on a recent morning was Kampong Speu High School, an hour west of Phnom Penh. There, seven survivors of the Khmer Rouge met the bus at the school to share their stories with students.