The observatory consists of oversized stone observation devices, which provide impressive accuracy due to their enormous dimensions. It is the biggest of five observatories, which Jai Sing II had built. The majority of the devices is typical for big observatories in the Islamic world. The most significant one, built by famous Ulugh Begh (1394-1449) in Samarkand has been an inspiring example for Jai Singh. But his instruments are unique as concerns precision, size and architectural perfection. At least, 120 years after the invention of the telescope they still provided amazingly and sometimes unmatched results.
Bottom left one of the twelve zodiac gnomes, in the
the hemispheres of the Jai Praksh Yantra, top right the little sundial.