Although the rebels who seized power in April 1975 were ousted just four years later, a civil war kept most visitors away until well into the mid-1990s. For years, splendours such as the World Heritage site of Angkor Wat were effectively out of bounds.
Yet tourism has bounced back.
Last year there were around two million visitors and by next year the authorities hope the figure will top three million. Increasingly, as tourists have returned to Cambodia to visit such wonders as the 12th-century temple complex near the town of Siam Reap, they have also found time to fit in locations associated with the Khmer Rouge.
Chief among these have been Tuol Sleng Prison in Phnom Penh, where up to 17,000 people were tortured and sent for execution, and the killing fields themselves, located on the edge of the city at Choeung Ek.
Even if it wanted to, Cambodia has not been allowed to forget its past.
A major legal process to try six former Khmer Rouge officials is proceeding under the oversight of the United Nations in a move that took more than a decade to agree.
Yet not everyone agrees that the Government should be using this dark period in the country's history to bring in foreign currency, however much they are needed.
Youk Chhang, who heads the genocide documentation centre, which brings together personal testimonies and documents from the Khmer Rouge era, said: "Using genocide to attract tourists is irresponsible. These [events] have to be preserved; they have to be documented.
"But if you allow this to be commercialised then you dehumanise and victimise us. For a long time we have been struggling to become something else."
The Government of Hun Sen, who once was a Khmer Rouge official, has identified 14 places at the remote hilly location it wants to bring to the attention of tourists.
As recently as 1998, the village near the Dangrek mountains was the final stronghold of the last remnants of the Khmer Rouge.
Among the obvious elements of interests will be the place where the French-educated Pol Pot was cremated after he reportedly suffered a heart attack.
Another spot to be promoted is the grave of Ta Mok, also known as "The Butcher" for his apparent ruthlessness, and who was the only Khmer Rouge leader not to be killed or else surrender to government forces.
Captured in 1999 after the movement disintegrated, he died in 2006 while waiting to be tried at the UN tribunal.
- INDEPENDENT