The Jantar Mantar is a collection of architectural astronomical instruments, built by Maharaja (King) Jai Singh II at his then new capital of Jaipur between 1727 and 1734. It was modeled after the earlier Jantar Mantar that was built in the capital Delhi. The Jaipur observatory is probably the best preserved of the 5 such projects that the Maharajah undertook.

The observatory consists of fourteen major geometric devices for measuring time, predicting eclipses, tracking stars' location as the earth orbits around the sun, ascertaining the declinations of planets, and determining the celestial altitudes and related ephemerides. Each is a fixed and 'focused' tool. The Samrat Yantra, the largest instrument, is 90 feet (27 m) high, its shadow carefully plotted to tell the time of day. Its face is angled at 27 degrees, the latitude of Jaipur. The Hindu chhatri (small cupola) on top is used as a platform for announcing eclipses and the arrival of monsoons.

Since its construction, the Jantar Mantar has been restored and declared a national monument by the government of India.The site of the Jantar Mantar is one of the most popular tourist attractions of Jaipur today. It is however, still used as an observatory by local scientists and is thought to be one of the best representatives of Vedic thought that exists today.

Visit Duration : 2 hours

Opening Time : 9:30 AM

Closing Time : 4:30 PM