Skycity

Sky City (Chinese: 天空城市; pinyin: tiānkōng chéngshì), or Sky City One, is an 838 m (2,749 ft) tall skyscraper proposed for construction in the city of Changsha, Hunan in south-central China. The prospective builders, Broad Sustainable Building, estimated it would take just 90 days to construct, but other estimates state that it will take 210 days to complete. If completed, it could become the tallest building in the world.