Oasis 21 is a Japanese man-made, environmentally friendly glass house, like a baseball-sized fish tank. It was designed and built by Hideki Casai and won the 2003 Solutia Award (for the author of the glass-based design). Oasis 21 is a boastful and dazzling landmark building in the local area, but also fully displays the concept of environmental protection. The uppermost layer is the "Water Cosmic Ship", all built by glass, is a large container for rainwater, rainwater can be used by the following other facilities. Fully display the link of natural energy recycling.