Last Updated on March 8, 2026

Visiting the S21 Prison and killing fields in Phnom Penh is something I think everyone who visits Cambodia should do. Cambodia is not just about culture, cuisine, and landscapes. In my opinion it also involves confronting the painful and dark history that the country endured during the Khmer Rouge regime. Day two of my time in Phnom Penh, the capital city of Cambodia, was dedicated to understanding this history, as I visited S21 and the Killing Fields. In this blog post, I’ll share my personal experience and provide some tips for if you are planning to visit these sights.

Estimated reading time: 13 minutes

Disclaimer: this article contains shocking images and text.

How to travel to S21 and the Killing Fields in Phnom Penh?

My day began at my hostel from where I booked a tuk tuk with Passapp to S21. Ordering tuk tuks myself was cheaper than booking a tour that included transportation. I needed a tuk tuk to S21, from S21 to the Killing Fields and from the Killing Fields back to the hostel. Arranging my own transportation also gave me plenty of time to see these places. Knowing that there is not a driver waiting for you was very nice, because I took quite some time at the museum and the Killing Fields.

If you are traveling from other cities in Cambodia to Phnom Penh, I recommend using 12Go to find the most affordable and comfortable transportation options.

My experience at the Tuol Sleng Genocide Museum

S21, also known as the Tuol Sleng Genocide Museum, is a former school turned into a prison and torture site by the Khmer Rouge (location on Google). The transformation of this ordinary school building into a place of horror is a dark reminder of Cambodia’s past. The prison housed innocent people, for example teachers, journalists, intellectuals, monks or people with glasses.

I rented an audio tour and visited the four main buildings that revealed torture chambers, torture attributes, photos of prisoners and survivors, remnants of clothing, mass cells, and even human remains. The prison was (as I said) intense to see. The audio tour indicated what could be seen in the room before I entered and gave a warning in case of extremely violent things. This way, I could decide for myself what I wanted to see.

– Building A

I started in Building A, which was the torture building. Here, many classrooms were turned into torture rooms with iron beds inside, one bed per classroom. The prisoners were tortured here 3 times a day until they gave in to write a statement. After this statement was written they were still transferred to the Killing Fields and killed. In some rooms there were pictures showing bodies on the beds. This is how the Vietnamese, the liberators, found the prison.

– Building B

As we walked from building A to B, we passed several playgrounds. Although children used to play here, the Khmer Rouge used it as torture devices. Unbelievable how they could think of this.

Building B was set up more as an education room. This room was intense to see and you may decide to skip it. The room has many photos of prisoners, of how they entered the prison (intake photos) and how some were found deceased. In addition, you can learn about the rise of the Red Khemr, the leaders and the ultimate goal.

– Building C

Building C was still in the most authentic state of all the buildings, but was covered in barbed wire. This was put up so that the prisoners could not kill themselves, as one had jumped from the third floor. Inside this building, I saw different types of cells like wooden cells, brick cells and group cells (up to 50 persons). It felt strange to walk around these cells, knowing all that had taken place here in the past. Most of the cells are so small. It was pretty intimidating to walk past all the cells.

– Building D

Building D was devoted to education. Here it was explained how the prisoners were tortured. Various instruments had been found and were on display. It was though to see. In addition to the instruments, there were many paintings hanging. These paintings were painted by someone who survived prison. And not just anyone. This person was just one of 12 people out of 18,000 who survived prison. Unbelievable….

In the last room of building D I saw more than 100 skulls. These were found in a mass grave next to the prison. At one point the grave was full and they started digging mass graves outside the city: the Killing Fields. Around 18,000 people died in the prison and many more were murdered at Phnom Penh’s killing fields, which I visited after S21.

More than 300 killing fields (mass graves) were eventually found in Cambodia. So can you imagine how many people died. Sources estimate that 2 to 3 million Cambodians were killed. At the time, a third of Cambodia’s total population.

My thoughts

I did have a hard time at S21, but I also felt that I had to do this. Not looking away, but visit the prison and give a donation afterwards. After all, the people of Cambodia are looking forward. I bought a book by a survivor inside the prison and am going to read it. I would like to deepen my knowledge even more.

Lunch and doubts

After visiting S21, I got lunch at a Circle K before continuing on to the Killing Fields. I still hesitated whether to continue to the Killing Fields, as I was already quite exhausted emotionally, but I decided to continue. The Killing Fields, officially known as Choeung Ek Genocidal Center, is located about 15 kilometers southwest of Phnom Penh (location on Google).

The Killing Fields

Once arrived at the Killing Fields, I bought an entree ticket and rented another audio tour. The audio tour painted horrible pictures of the brutality that happened here. I learned how prisoners were placed kneeling and blindfolded in front of mass graves before being ruthlessly murdered. To save bullets and make as little noise as possible, they were hit hard on the head with an object. Then someone stood in the mass grave and slit the throats. Some graves contained more than 300 prisoners. The details of the audio guide also included the use of a tree to brutally end the lives of children and babies. I stood in front of the graves and the tree, feeling speechless. It was really sad to hear and see all of this.

On the grounds you will also find a large natural lake that you can walk around. For me, it was a nice place to sit on a bench to reflect on everything I had seen in peace.

These days you can still see some pieces of clothing and bones in the fields. After the genocide, it was not possible to excavate all the remains, because some kind of poison was thrown into the graves by the Red Khmer. If you dig this up and inhale it, you probably will die. Because of the heavy rains in Cambodia, every now and then pieces of clothing and bones still come up. Every month a group of volunteers collect the remainings and place it in a large monument which is located at the entrance. The monument is 17 stories high and consists of a collection of found skulls, bone remains, clothing and other objects. A commemoration is held every year.

The Day of Remembrance: May 20th

Each year, 20 May (the day when the Khmer Rouge began their collective program in 1973) intends to remember the painful sorrow caused by the Khmer Rouge genocidal regime. In February 2018, the government of Cambodia adopted 20 May as a national holiday, the ‘Day of Remembrance’. I hope you (like me) will make the effort to briefly remember this event and its victims every year on May 20.

Tips for visiting the S21 Genocide Museum and Killing Fields

1. Prepare emotionally: The experience was emotionally heavy for me, so mentally prepare yourself for the intense stories and visuals.
2. Dress comfortable and respectful: Wear comfortable clothing and shoes as you will be walking a lot. Please also dress modestly and respectfully, as both sites are places of remembrance. Wear long trousers and cover your shoulders.
3. Bring water and snacks: Ensure you stay hydrated during the visit and pack some snacks to keep your energy up.
4. Audio guide: Consider renting audio guides at both locations for a more in-depth understanding of the history.
5. Combined Ttckets: Some tour operators and ticket booths offer combined tickets for S21 and the Killing Fields, providing cost savings.
6. Plan sufficient time: Allocate enough time for both sites. Each deserves a few hours for a thorough exploration.
7. Respect local customs: Respect the local customs and rules at the sites. Avoid disruptive behavior and be mindful of the somber atmosphere.

Tour to the killing fields and S21 Genocide Museum

Some tour operators, ticket booths and ho(s)tels offer combined tickets for S21 and the Killing Fields, providing cost savings. Many offer half-day or full-day tours that include transportation. Below you can find some options via GetYourGuide. I use this online platform a lot when traveling.

Accommodation in Phnom Penh

Phnom Penh has a variety of accommodation options to suit different preferences and budgets. Here are some recommended areas and accommodations in Phnom Penh:

– Budget accommodation

There are guesthouses and hostels in various parts of the city. Popular options are Mad Monkey Hostel, Onederz Cambodia or La Chronique Hotel. I’ve stayed in a private room in Onederz and really enjoyed it. There was a rooftop pool, restaurant and bar available.

– Mid-range accommodation

Close to the Tonle Sap River and in the city centre are plenty of mid-range accommodations available. Popular options are the White Mansion or Duong Chan Hotel.

You can also rent an apartment if you like. AMATA Residence or Season Residence are great mid-range options.

– Luxury accommodation

BKK1 (Boeung Keng Kang 1) is a trendy and upscale district in Phnom Penh. Recommended hotels are Pavilion Hotel, Plantation Urban Resort & Spa, and Jungle Addition.

Conclusion

Visiting the S21 and Killing Fields in Phnom Penh was a sad, but essential experience to understand the depth of Cambodia’s history. It was a very intense day to have seen and heard all of this. It is very good that the story is still being told, so that we all understand how one person can change and destroy a country. The stories told within the prison and outside in the fields are important to hear and see, so we create awareness to prevent such atrocities from happening again.

If you have any questions about the above mentioned information, please let me know in the comment section below. I’m happy to help you. Safe travels!

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This article is featured on GPSmyCity. To download it for offline reading or to create a self-guided walking tour of the attractions highlighted here, go to Walking Tours in Phnom Penh.

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