While entering the exquisite city palace one gets the great warm welcome through confusing Jantar Mantar, the Yantralaya of Sawai Jai Singh , the last great classical astronomer in India. Yantras are the unique modernistic structures designed by Sawai Sai Singh and purposely built by experts to observe the movements of sun, moon, planet and the stars.This is the largest of five observatories founded by him in 1716.

The others are at Delhi, Ujjain, Mathura and Varanasi. It's massive masonry instruments are of an extraordinary precision and can still be used to measure local time, the sun's declination, azimuth and altitude, the declination of fixed stars and planets and also to determine the time of an eclipse of the sun.