Jantar Mantar is very popular among tourists and the people of Delhi. The structure is another great masterpiece of  Indian architecture  which shows the  scientific acumen of ancient India . Jantar Manter is situated at Parliament Street, very close to Connaught Place. Jantar Mantar is also called Delhi Observatory. It is maintained by the Jaipur government because it was built by  Maharaja Sawai Jai Singh II  of Jaipur in 1710 A.D. It is a remarkable structure which consists of fourteen geometric devices used for measuring time, forecasting weather changes, predicting behaviour of planets and finding extraterrestrial altitude. All these devices are fixed structures and point to a specific direction. The largest device or instrument is the Samrat Jantar which is 90 feet high and its shadow is plotted in such a manner so that is shows the exact time of the day. Any weather change or the onset of monsoons can be ascertained by the Hindu Chhatri, which is a smal...