UNESCO World Heritage site featuring the world's largest stone sundial and 19 astronomical instruments built by Maharaja Sawai Jai Singh II.
Jantar Mantar is an astronomical observatory built by Maharaja Sawai Jai Singh II, the founder of Jaipur, between 1728 and 1734. It features the world's largest stone sundial and is a UNESCO World Heritage site.
The observatory consists of 19 astronomical instruments for measuring time, predicting eclipses, tracking stars, and determining celestial altitudes. These massive structures were built with locally sourced materials and designed to withstand the test of time.
The most impressive instrument is the Samrat Yantra (Supreme Instrument), a 27-meter-tall sundial that can tell time with an accuracy of about two seconds. Other notable instruments include the Jai Prakash Yantra, which can map the position of stars, and the Rama Yantra, used to measure the altitude and azimuth of celestial bodies.
Maharaja Jai Singh II built five such observatories across India, but the one in Jaipur is the largest and best preserved. The observatory demonstrates the king's passion for astronomy and his scientific knowledge, which was far ahead of his time.
