Sri Yantra
Quote, from Wikipedia: "The Sri Yantra or Sri Chakra is a form of mystical diagram (yantra) used in the Shri Vidya school of Hindu tantra. It consists of nine interlocking triangles that surround a central point known as a bindu. These triangles represent the cosmos and the human body. Because of its nine triangles, Sri Yantra is also known as the Navayoni Chakra."