The Water Cube was specially designed and built by a consortium made up of PTW Architects (an Australian architecture firm), Arup international engineering group, CSCEC (China State Construction Engineering Corporation), and CCDI (China Construction Design International) of Shanghai. The Water Cube's design was initiated by a team effort: the Chinese partners felt a square was more symbolic to Chinese culture and its relationship to the Bird's Nest stadium while the Sydney-based partners came up with the idea of covering the 'cube' with bubbles, which symbolizing water. Contextually, the Cube symbolizes Earth, while the circle (represented by the elliptic stadium) represents heaven, a common motif in ancient Chinese art.