I went to Jantar Mantar, Delhi on 11th June 2014 at 9:00 AM. It is located at Sansad Marg, Connaught Place, i.e the heart of Delhi. It is one of the five observatories built by the Maharaja of Jaipur – Sawai Jai Singh II. The primary purpose of the observatory was to compile astronomical tables, and to predict the times and movements of the sun, moon and planets. There are 13 astronomical instruments, out of which 1 is samrat yantra, the sun dial. Samrat Yantra calculates time of the accurately. Jantar Mantar can be reached easily by delhi metro, nearest metro station is patel chowk.