水立方, also known as the Beijing National Aquatics Center, is a famous swimming and water sports venue located in Beijing, China. It was built for the 2008 Summer Olympics and is renowned for its unique architectural design, resembling a cube made of bubbles. The structure is primarily made of ethylene tetrafluoroethylene (ETFE), which allows natural light to illuminate the interior. The facility has a seating capacity of around 17,000 spectators and features multiple swimming pools, including an Olympic-sized pool. After the Olympics, 水立方 has been repurposed for various events and activities, including public swimming and water sports competitions.