The words Jantar and Mantar derive from Sanskrit words Jantra and Mantra that mean ‘instrument’ and ‘calculate’ respectively, which makes the meaning of Jantar Mantar as “a calculating instrument”. Designed for the observation of astronomical positions with the naked eye, they embody several architectural and instrumental innovations. The structure in Jaipur is a complex of nineteen architectural astronomical instruments, and is still running and being used for calculations and teaching. It is an expression of the astronomical skills and cosmological concepts of the court of a scholarly prince Sawai Jaisingh II at the end of the Mughal period. It is used to observe and study the orbits around the Sun. Some of the structures here were built in stone and marble, and some in bronze. One of the remarkable aspects of Jai Singh’s observatories is that each of the 5 sites is distinctly different in size, layout, and style. While the instruments he designed are essentially the same in principle, the versions at different sites vary in size, materials, and construction.