The unfinished shell of Hitler's Nazi holiday paradise – the Colossus of Prora – is to be gutted and redeveloped into luxurious beachfront flats, a high-end hotel and a day spa.

The site sits over 2.8 miles of beachfront on the Baltic island of Ruegen and was begun by the Nazi's "Strength Through Joy" leisure organisation, the Daily Mail reports.

The complex was intended to entertain up to 20,000 holidaymakers at a time. Work on the site began before the Second World War, but was abandoned midway through its construction as funds and resources became stretched.

For decades after the war, the incomplete resort sat empty before it was eventually turned into housing and training facilities for East German soldiers. Now developers are attempting to complete the complex, part of which will be named "New Prora". But work on the site has been the subject of intense scrutiny and criticism.

Some critics say that the renovation fulfils the Third Reich’s plan to turn the area into a tourism hub, The Independent reports.

"These are not harmless buildings," Jurgen Rostock, co-founder for the Prora documentation centre says. "The original purpose for Hitler was the construction of [a resort] in preparation for the war to come. This way of dealing with the building trivialises it and affirms the Nazi regime."

Kathrin Lange, one of the site's real estate brokers, is also aware of the controversy around the revival of the former Nazi holiday and leisure project. "Prora is an experiment," she told Die Welt newspaper. "It is something for the risk-tolerant investor."

Some historians argue that there is some merit in preserving the site, particularly as the buildings encapsulate some of the best architectural practices from the era, which brought together Art Deco and classical Roman design. However, as Vocativ notes, many find it impossible to separate the site's architecture from its politics.

"The buildings themselves seem to give life to the Third Reich's mythology about happy workers, clocking in and out for the greater good of the nation. And that will be hard to erase, regardless of how many Germans come to the area for shopping and sun-bathing," Vocativ concludes.