In the foreground is the main entrance to Hoa Lo Prison, with tourists standing on the sidewalk. At back is the modern new building that has been built on the bulk of the space formerly occupied by the prison. Hoa Lo Prison, also known sarcastically as the Hanoi Hilton during the Vietnam War, was originally a French colonial prison for political prisoners and then a North Vietnamese prison for prisoners of war. It is especially famous for being the jail used for American pilots shot down during the Vietnam War.