Jantar Mantar, constructed by Jai Singh II is one among the five observatories. The main attraction of the observatory is the Sundial which is recorded as the biggest in the world. The Mantar is built of stone and brass using the ancient architectural principles and there are 19 instruments in the Mantra to observe the astronomical positions. This UNESCO World Heritage site is an amazing example of Ptolemaic positional astronomy. The visiting timing of the Mantar is between 9 am to 5 pm.