... Choeung Ek is one of Cambodia's handful of memorials of the Khmer Rouge genocide that, between 1975 and 1979, claimed the lives of nearly 2 million citizens - a third of the nation's population then.

Van and Bei - and 396 fellow villagers from across the country - are here on a two-day, all-expense-paid educational trip organized by the Documentation Center of Cambodia (DC-Cam), a leading research institution on the killing fields.

Mention Cambodia, and the first image that most Westerners think of is heaps of skulls. So it may sound peculiar that numerous survivors - and some perpetrators - themselves have yet to learn about the true extent of the killing fields. During the Khmer Rouge era, rural Cambodians were isolated and resigned to fates imposed by tyrannical overlords. Many still don't understand why they and their families were condemned to extreme suffering, let alone murder, by the Khmer Rouge who proclaimed themselves the liberators of the dispossessed. And governments since have done little to educate them about the period.

"Most survivors living in rural communities have only isolated memories of atrocities," explains Ly Sok Kheang, a researcher for DC-Cam, who is escorting the villagers around memorial sites. "Many don't even know what happened in neighboring provinces."...