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A lot of travelers going to Cambodia don’t even stop by Phnom Penh, because they feel like there’s nothing to do there. However I recommend staying there for a few days, at least to visit the Tuol Sleng genocide museum (formerly prison S-21), but also Choeung Ek, the killing fields of the Khmer rouge. But what’s that, the Tuol Sleng genocide museum? And Choeung Ek, the killing fields?

Quick history class of Cambodia
Quick history class. Cambodia was part of Indochina, the former French colony. After its independence, Cambodia had to face another problem, the Vietnam war. Cambodia was not directly involved in this war, but the USA also bombed Laos and Cambodia, to prevent the communists in Vietnam from getting supplies in those countries (via the Ho Chi Minh trail). The Khmers rouge, who were communists, were first seen as heroes by the local population when they managed to get rid off the Americans progressively.

Invasion of the Khmer rouge troops
But Cambodia was about to live one of the worst eras of its history. On April 17th, 1975 the Khmer rouge troops captured Phnom Penh and ordered the population to evacuate the city “just for a few days because of the threat of imminent American bombing“. The locals were first delighted with the coming of the Khmer rouge. But they became disillusioned really fast. Those who were at the hospital were evacuated by force, families were separated, the population was divided in several groups and those who didn’t want to leave their house were killed.

New political regime
The Khmer rouge leader, Pol Pot, wanted to create a new political regime. The country won’t be called Cambodia anymore, now it’s Democratic Kampuchea. We’re not in 1975 anymore, we’re in year zero of a new era. The Cambodian language was changed, but most importantly the population was about to be “purified”. From April 17th 1975 to January 7th 1979, studies estimate 3 millions innocents (out of 8 millions inhabitants in the country!) were killed in Cambodia.

How to get rid of millions of people? The Khmer rouge soldiers locked up the population in prisons, they tortured them, made them sign false confessions before taking them to the killing fields to kill them. It lasted almost four years, and it stopped in January 1979 when the Vietnamese army invaded Phnom Penh and Cambodia. During those four years, there were prisons and killing fields all over the country.
Nowadays, if you go to Phnom Penh, it’s possible to visit what was prison S-21, now called the Tuol Sleng genocide museum. This is where the Cambodians were locked up and tortured. It’s also possible to visit Choeung Ek, a killing field, located 15 kilometers (10 miles) away from the capital. Definitely not for the faint of heart.
Tuol Sleng genocide museum
Murder of the intellectuals
Before being the prison S-21, Tuol Sleng was a high school. But with the Khmer rouge running the country, this high school was turned into a prison. From 1975 to 1979, between 12 and 20000 Cambodians were locked up and tortured there. Duch, the director of the prison S-21, oversaw the logistical organization of the prison. He was also giving orders to the torturers, the Khmer rouge soldiers. Anyone wearing glasses, having a pen, knowing how to speak a foreign language, the doctors, engineers, intellectuals… were killed because they represented a threat to the regime.

Torture of the local population
The poor victims, under torture, had to sign false confessions before being sent to Choeung Ek to be killed. How come soldiers were able to torture fellow Cambodians? You need to know something, most of them were peasants from 10 to 20-years-old, with no education and not even knowing how to read. Most of them were peasants who grew up in remote places of the country, sometimes in the jungle, and who had never visited a city before.
Therefore it was easier for the Khmer rouge leaders to manipulate them, and it also explains why Pol Pot, the Khmer rouge leader, feared the intellectuals. Duch, the director of the prison S-21, asked the soldiers to learn how to torture people with the animals in the surroundings (especially stray dogs). By the way, Duch used to say they were torturing people to make them talk, to have a response, not for pleasure.

Visit to Tuol Sleng
But let’s focus on the visit of the Tuol Sleng genocide museum. Tuol Sleng is divided into four buildings, and there’s a central courtyard. I give all the info at the end of the article, but I strongly recommend taking the audioguide. Otherwise, you won’t understand what you see. A young Cambodian guy, speaking proper English, guides you through Tuol Sleng. The first thing we see is the central courtyard, and 14 graves there, those of the last 14 people they found in Tuol Sleng… Next to the graves, there’s a seesaw turned into an instrument of torture (I won’t show any hardcore images in the article but believe me, some things are not easy to watch there).

Building A
Building A is the one where you’ll see the torture rooms. Before being the prison S-21, those torture rooms were classrooms. In the different rooms, there’s a metal bed, and nothing more. Victims were fastened to the different beds and tortured. It’s forbidden to take pictures in those rooms.

Building B
Building B is the one where you’ll see photos of the victims. The Khmer rouge took pictures of every newcomer in Tuol Sleng, they measured them and give them an ID number. The Khmer rouge were also taking pictures of victims who were already dead when arriving. You’ll notice some victims are actually Khmer rouge soldiers. Indeed, during the last few months before the regime collapsed, the Khmer rouge leaders were so paranoid that they suspected some of their own soldiers of treason and they were killed.

Building C
Building C is the one where the victims were locked up. This is when you realize prisoners were living in tiny cells. There’s a second room with several documents exhibited. Most of them are related to Pol Pot and the very few Khmer rouge leaders who are still alive today (among them Duch, the director of the prison S-21).

Building D
Building D is the one where you’ll see many documents related to this dark era of Cambodia history : pictures of Phnom Penh before/after Khmer rouge took over the country, maps showing the population movement those years, but above all you can see Vann Nath paintings. Vann Nath was one of the numerous Cambodians who stayed in Tuol Sleng. But he’s one of the very few survivors (we estimate 12 people survived Tuol Sleng).
Since he was a very good painter, after the end of the regime, Vann Nath painted for the justice to show what was going on in Tuol Sleng. It’s horrible to watch the torture scenes but thanks to him, we know what happened in the prison S-21… If you really want to see, type “Vann Nath paintings” on Google and you’ll see Vann Nath paintings, exhibited in Tuol Sleng. Not easy to watch… Vann Nath passed away in 2011.

Survivors of Tuol Sleng
How did he survive? Some Cambodians with very specific skills could be useful for the Khmer rouge regime, and they were spared. That’s why they didn’t kill him, he was forced to paint Pol Pot portraits. But the Khmer rouge probably didn’t realize this would turn against them later on. We’re a bit shocked after visiting Tuol Sleng genocide museum. Just before leaving, I spotted an old man in front of a stall.
It’s Chum Mey, one of the 12 survivors! He’s here! There was a stall with his book on sale, and he was quietly waiting. I greeted him and smiled. He smiled back. And I left, not acting like a groupie and asking for a picture. From what I heard he’s not always there, so I was lucky to see him. Sometimes Bou Meng, another survivor, is present but I didn’t see him.

The Tuol Sleng genocide museum was opened in 1980, a year after the end of the Khmer rouge regime. Many locals went there, seeking information… to find horrible photos of relatives who were killed there (yep, the photos are exhibited). They found out with horror instruments of torture, skulls of dead people… The Tuol Sleng genocide museum was just the first part of the massacre. Then the Khmer rouge had to kill the poor innocents in killing fields. The day after visiting Tuol Sleng, I went to Choeung Ek, one of the most famous killing fields, located 15 kilometers (10 miles) away from Phnom Penh.
Choeung Ek (the killing fields)
Massacre of the local population
Before being a killing field, Choeung Ek was a peaceful Chinese cemetery… The poor Cambodians who signed false confessions in Tuol Sleng were then taken to Choeung Ek, where all the executions took place. In Tuol Sleng, the Khmer rouge soldiers lied to them and kept saying they were transferred to another prison. They wanted to avoid any panic reaction. The victims didn’t know they were about to be executed… 20000 people died in Choeung Ek…

The victims were transferred from Tuol Sleng to Choeung Ek during the night, to avoid arousing suspicion. The victims were arriving blindfolded, and they were then killed hit by a shovel or the soldiers slit their throats. But they were never shot dead by the soldiers, it was too noisy and bullets were too expensive. That means victims suffered a lot before dying, and big speakers were playing loud music to cover the victims’ moans.

DDT
Once they were dead, victims were thrown away in a mass grave. The soldiers sprayed DDT on the dead bodies to conceal the smell (because of the decomposition of the bodies). It was also a way to avoid suspicion from workers in the surroundings, who were also using DDT as an insecticide. DDT also allowed to kill for good those who were still alive in the grave.

More and more dead bodies
The massacre lasted several years. At first, around 200 citizens were killed each month in Choeung Ek. Victims were killed the same night they arrived on the spot. But with all the paranoia and the growing number of locals waiting to be killed, during the last months, 300 citizens were killed every day in Choeung Ek. They were waiting for one or two days after arriving there, before being killed.

Visit to the killing fields
Once again, when you arrive in Choeung Ek, get an audioguide. A young Cambodian guy will guide you and explain exactly what happened there. One of the hardest part of the visit takes place towards the end. You’re in front of a tree. It’s the killing tree. Babies were caught by the legs and their heads were smashed against the tree. They were then thrown away in the grave next to the tree, with all the women. They were all naked in the mass grave.

The big stupa
In the center of Choeung Ek, you can see a big stupa erected in 1988 in memory of the victims. There are 17 levels in the stupa, in reference to April 17th 1975. We cannot get in the stupa but from the outside we can see many bones in it. They are sorted by category, age of the victims… Every year on May 20th, date of the new regime instituted by Pol Pot, there’s a ceremony. It’s a commemoration of the victims. Locals make offerings and historical reconstructions.
The Choeung Ek museum
In Choeung Ek, you can also go to a museum not far from the entrance. In this museum, they show a movie presenting how Choeung Ek was when they discovered the place. In this museum, they also exhibit documents and weapons used by the Khmer rouge, and we can even see the Khmer rouge uniform.

End of the Khmer rouge regime
Those mass killings ended when the Vietnamese army invaded Phnom Penh on January 7th 1979. The Khmer rouge leaders fled towards the border with Thailand. Choeung Ek was discovered by accident by a peasan who was going home. He found a tree with hairs and cerebral substance on it. Afterwards, the excavations of Choeung Ek allowed to find close to 9000 bones out of approximately 20000 victims. Out of 129 mass graves. 86 of them were excavated. In one of them, they found 166 headless bodies.
Those were Khmer rouge soldiers suspected of treason (Pol Pot was very paranoid). In another mass grave, they found 100 bodies of naked women and babies, next to the killing tree. Survivors started to testify and talked about cases of rape and cannibalism… Over time, they discovered 190 prisons like S-21 in the country, and around 300 killing fields in Cambodia.

What happened to the Khmer rouge leaders? Again, you need to know something. The international community supported the Khmer rouge regime until 1991! It’s politics, due to the cold war. China and Vietnam were accusing this movement of genocide but for the Westerners, China and Vietnam were the nasty communists. Moreover, the US still had a vivid memory of the Vietnam war they lost, that war was still stuck in their throats… Therefore the US, the UK, France… were supporting the Khmer rouges!

Khmer rouge leaders in jail
After the regime collapsed, the Khmer rouge leaders fled towards the border with Thailand, and they lived in the jungle or in small villages. Many of them died over the years. Pol Pot, the leader, mysteriously died in 1998. Some people say he was poisoned by an ex-goon but we’ll never know. The first one justice caught with was Duch, the director of the prison S-21. An Irish photographer recognized him in 1999, in a Cambodian village. He was judged and sentenced to life imprisonment. He died in 2020. During his trial, they took him back to Choeung Ek, next to the killing tree. He kneeled down and started crying, apologizing for all the bad things he did.

Four other Khmer rouge leaders were finally arrested in 2007, and their trial took place in 2011. Khieu Samphan and Nuon Chea were sentenced to life imprisonment, they’re still locked up. Ieng Sary died in 2013 during the trial. His wife Ieng Thirith was ruled mentally unfit to stand trial (because of Alzheimer disease), and she was released in 2012 for insanity. She died in 2015. All of them put the blame on the subordinates despite the evidences.

While we’re at it, what about the subordinates? After the fall of the regime, they were asked how they could have been so cruel with men, women and children. Most of them said they were just obeying orders of the leaders… I said it earlier, the subordinates were peasants with no education, but still…

I left Choeung Ek thinking about all the things I saw. Walking in the streets of Phnom Penh, everytime I passed by a man of a certain age (at least 50 years old), I kept thinking “It might be one of those subordinates during the Khmer rouge era. Or a survivor of this massacre“. Same thing when I saw an old woman. Maybe a survivor of this terror.
There were other massacres in history : Americans with the Apaches, the Nazi in Germany, Pinochet in Chile, Tutsis and Hutus in Rwanda, rohingyas in Myanmar, the Armenian genocide… Maybe there will be other ones in the future. But going there, seeing shocking photos, listening to horrible stories, it does something to you. I recommend you to visit Tuol Sleng and Choeung Ek. But I saw people crying there. Now you know. Don’t forget to check out my post listing the best places to visit in Cambodia!
Where is the Tuol Sleng genocide museum
The Tuol Sleng genocide museum is located in Phnom Penh, it’s not hard to get there.
Tuol Sleng genocide museum price
It’s $5 to get in but as I said, take the audioguide. Otherwise you’ll miss a lot of information. With the audioguide, it’s $8 to get in.
How long is the visit of the Tuol Sleng genocide museum
Allow 3 hours to visit Tuol Sleng.
Where is Choeung Ek
Choeung Ek (the killing fields) is located 15 kilometers (10 miles) away from Phnom Penh. You can rent a scooter to get there but from what I heard, the killing fields are not easy to find. The best way to go there is to ask a tuktuk to take you there, and bring you back in town after the visit. The round trip costs $12.
Choeung Ek price
It’s $6 to get in Choeung Ek with the audioguide.
How long is the Choeung Ek visit
Again, allow 3 hours for the visit.
Best time to go to Tuol Sleng and Choeung Ek
Either for Tuol Sleng or Choeung Ek, you should ideally go there in the morning. In the afternoon both places are crowded and it’s scorching outside. I suggest you to not go on both places the same day, and you should start by Tuol Sleng. If you don’t have time, you can go to both places the same day, but that means you’ll visit one of them in the afternoon. Plus knowing what you’re going to see, that’s a lot for your mental health in one day…
Tuol Sleng and Choeung Ek tips
- Wanna know more about the killing fields? Get this book then, written by a survivor of the killing fields!
- Traveling soon? Check out my travel resources page! This list of travel accessories can also be useful!
- As usual, don’t leave home without a travel insurance! Here’s why you should buy travel insurance!
- Want a tailor-made trip to Cambodia? Get a free quote here!
- Cambodia is a cheap travel destination!
- Click here to check the latest flight prices. And click here to book a hotel room.
- Always use a VPN when traveling. I use ExpressVPN and I love it! Here’s why use a VPN when traveling!
Very well written. Engaging, sad, I had no idea. Thank you for sharing this part of history.
Thanks!
Wow what a power blog. My mum visited a few years ago and said how it sickened her and we have just visited Auschwitz and Birkenau, so can relate to the atrocities that you talk about. It’s important that pieces like this are ‘out there’ to remind us about the importance of compassion and resolution not war.
Thank you! Yeah let’s not forget, I thought a lot about it for several days after visiting those places.