The prison was originally built by the French to house political prisoners and later used for POWs during the Vietnam War. In 1999 a Hilton Hotel opened in Hanoi and was carefully named the Hilton Hanoi Opera Hotel.

Rounding out the list of top 10 include Alcatraz- the most famous prison in the US

Tower of London, in UK

Devil's Island in France

Chateau d’If in France

Goree Island in Senegal

Robben Island in Cape Town, South Africa

Elmina Castle in Ghana

Port Arthur in Tasmania, Australia

and Tuol Sleng Genocide Museum in Cambodia.