Khmer Rouge, genocide, S-21, Choeung Ek: understanding 1975-1979 before your visit

Planning to visit the Tuol Sleng Museum (S-21) or the Killing Fields of Choeung Ek in Phnom Penh? These are among Cambodia's most visited sites, but their emotional weight is immense. Without historical context, a visit risks being confusing, even disrespectful.

Between 1975 and 1979, the Khmer Rouge regime caused the deaths of 1.7 to 2.2 million Cambodians—a quarter of the population. This guide provides you with key chronological markers, essential figures, and conduct guidelines so your visit is informed and respectful.

On April 17, 1975, the Khmer Rouge led by Pol Pot took Phnom Penh after a five-year civil war. They imposed a radical Maoist agrarian ideology: abolition of currency, private property, schools, and hospitals. The entire urban population was forcibly displaced to the countryside—2 million Phnom Penh residents evacuated in three days.

Intellectuals, religious figures, and ethnic minorities (Chams, Vietnamese, Chinese) were systematically targeted. Forced labor, famine, and summary executions killed one in four Cambodians. The regime fell on January 7, 1979, overthrown by the Vietnamese army.

The CETC tribunal (Extraordinary Chambers in the Courts of Cambodia) sat from 2007 to 2022. It convicted three senior leaders: Duch (S-21 director), Nuon Chea (chief ideologue), and Khieu Samphan (head of state). Cost: $350 million. The outcome was considered mixed: only three convictions for mass crimes, near-total impunity for mid-level cadres.

Compared to other memorial sites like Auschwitz-Birkenau (Poland) or the Holocaust Memorial in Washington, S-21 and Choeung Ek offer a raw, minimally curated immersion. At S-21, torture chambers remain as they were, with iron beds, instruments, and victim photographs. At Choeung Ek, the ossuary containing victims' skulls is visible.

What strikes visitors: the absence of distance. Unlike highly designed Western museums, the reality here is raw. For European visitors, it's unsettling but profoundly moving. Plan 3 to 4 hours for both sites (allow 30 minutes by tuk-tuk between them). The French audio guide is good quality and highly recommended.

• Before you go. Read a summary of the history (this article is sufficient). Watch the documentary S-21, the Khmer Rouge killing machine (available online).
• On site. Absolute silence in the rooms. No selfies, no photos in torture chambers (photos permitted in the courtyard and outside). Turn off your phone or put it on silent.
• Audio guide. Get it at the S-21 entrance ($3). It lasts about 2 hours and provides essential context.
• Dress code. Dress soberly (shoulders and knees covered). Bring water, a hat, as it's hot and the visit is long.
• After the visit. Allow yourself decompression time. Many visitors leave shocked. A quiet café in the BKK1 neighborhood helps you process.

• Visiting without preparation. Arriving without context makes the visit confusing and less respectful.
• Taking smiling selfies. This is perceived as deeply disrespectful by Cambodians. Photos are tolerated with discretion, but no joyful poses.
• Skipping the audio guide. Without it, you won't understand the camp's organization, prisoners' fates, or the tribunal's workings.
• Underestimating emotional impact. The visit can be distressing. Don't schedule anything demanding immediately after.

This visit is for anyone wanting to understand contemporary Cambodia. The genocide shaped the country's society, politics, and even economy. For expats and long-term travelers, it's an essential step to grasp intergenerational trauma and Cambodian resilience.

It's not recommended for young children (under 12) and highly sensitive individuals. For others, it's a necessary experience, to be done once. It gives depth to your stay that you won't find anywhere else.