The Jantar Mantar Observatory in Jaipur is amazing not for its high-end precision astronomical instruments, but for its various strange stone sculptures, including 19 architectural astronomers - sundials, constellations, etc., of which the "Stone Sundial" is the largest sundial in the world. Using astronomical celestial coordinates, the horizon-zenith local system, the equatorial system and the ecliptic system, these instruments can observe astronomical data with the naked eye. Every instrument in the Observatory has its own unique uses, such as measuring the position, altitude and azimuth of stars, and calculating solar eclipses. All kinds of observation instruments can still be used by astronomers. The construction of the Observatory shows the amazing wisdom of ancient India. This makes the Observatory very famous as a world cultural heritage.