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If you're ever traveling to Belgrade, Serbia, be sure to get a workout in here. This building is the "Danube Flower" and it began its life way back in the early 1970's as a Russian Communist outpost only to later lay abused and abandoned during the country's civil war of the 1990's.
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Just recently, it's been fully renovated and turned into a state of the art fitness center.
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Amazing facts: The space sits fifteen feet above the river and walkway below, a glass sandwich really between the towering concrete top and bottom. The entire building is based on 7.3 meter triangles and at its heart, boasts a ceiling consisting of 390 backlit panels that bounce the sun's rays off a highly reflective resin floor and emanate the space with light.