Jantar Mantar in Jaipur, is the most famous of five observatories built by Sawai Jai Singh in India. The Jantar mantar is a mis-prounounciation of Sanskrit word Yantra Mantra. It was built to check the astronomical observation at Jaipur. The Jantar Mantar at Jaipur was conceived as a quest for discovering the mysteries of the Cosmos .The sun dial of Jantar mantar is one of the major tourist attraction

Sawai Jai Singh sent his ambassadors to all parts of the world before starting the construction of this observatory. The ambassadors returned with many manuals on astronomy containing cutting-edge technological information. One of these manuals was a copy of La Hire's "Tables". The king ordered the observatory to be built according to the details contained in this manual.
 

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