Locals of Montenegro are furious after plans to transform a former WWII concentration camp into a high-end luxury resort were approved by the government.

Mamula Island was home to thousands of prisoners during the reign of fascist Benito Mussolini from 1942 until the end of the war.

More than 130 Serbs from Croatia, Montenegro and Bosnia and Herzegovina were killed inside Mamula, an ancient fort on a tiny islet off the coast of Montenegro.

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The fort, built in 1853 by Austro-Hungarian general Lazar Mamula, takes up 90 per cent of the islet’s land, with still-preserved prison cells visited by families of prisoners today.

But now that plans are approved, Mamula will be transformed into an exclusive resort complete with nightclub, VIP area, beach club and a water sports centre.

A promotional website imagines the Mamula resort before and after construction, with renders showing much of the fort filled with a fake beach.

A fake beach will fill the majority of the fort. Photo: Sima Multimedia

The response from locals has been one of outrage, particularly from those whose relatives suffered inside Mamula’s walls.

Jovanka Uljarevic, whose grandmother was a Mamula prisoner during WWII, said the resort (which promises a “party ambience”) would betray the fortress’ history.

“The Orascom project would ruin every memory of Mamula and what it really was,” Jovanka told the Balkan Investigative Reporting Network, BIRN.

Olivera Doklestic, who had three members inside Mamula, told the website: “The history of the island and its fortress must be at the centre of its adaptation. A luxury resort is not an adequate solution.”

Despite Orascom’s promise to feature a history museum and remembrance room within the resort, new renderings feature neither.

“The project will be sympathetic to the local architecture and will completely preserve the historical value of the island,” said the company on its website.

An unsuccessful protest was also mounted by former UN Secretary General Boutros Boutros-Gali, who sent a letter to the president of Montenegro’s parliament suggesting “additional thought be given to this matter and alternative possibilities for the use and adaptation of Fort Mamula”.

“We feel called upon to propose that Fort Mamula, originally built for war purposes and mostly used as a prison for internment, torture and executions during the two World Wars, be transformed into a facility and institution of peace and international cooperation,” read the letter, also signed by an ex-UNESCO director.

Mamula will keep its moat entrance. Photo: Sima Multimedia

Locals are also said to be unhappy about the rental price offered to Orascum, which is paying just $A2.30 per square metre on the islet – less than half the amount charged for fruit market stalls in the area.

However, a number of locals have expressed their support, particularly as the landmark is deteriorating with no one willing to front the money to preserve it.

Swiss/Egyptian company Orascom have been given a 49-year lease, and promise to create 200 new local jobs with the project.

Plans show a nightclub and water sports centre but no historical museum as promised. Photo: Sima Multimedia