The museum is the once prison that contained many people who were subsequently killed. Once a school, the museum offers a humbling account of the genocide. You can walk in the torture rooms and cells, and speak with some of the still living survivors of the tragic era. Highly recommend a tour guide to take you around this site and the Killing Fields to get the full picture. There are a couple of survivors that will share their story with you about how they survived. Buy their books or souvenirs to help support them.