Jantar Mantar

The world-renowned astronomical observatory, Jantar Mantar, in Jaipur is one of the five astronomical observatories built in the 18 th century by Maharaja Jai Singh II, the genious who built Jaipur City. One of the major landmark of the Jaipur city, it is a unique building on its own that differentiate Jaipur from other cities. Among the five observatories, Jantar Mantar is the best preserved. The open-air observatory with 18 instruments in all, erected between 1728 and 1734 (many of Maharaja Jai Singh II's own invention), consists of a dozen-odd metal and masonry structures used for astronomical calculations.

Literally known as 'Instruments for measuring the harmony of the heavens' each instrument of this observatory is used for a particular function and gives an accurate reading. Some are still used for forecast.

There are 18 different Yantras placed in clockwise at the observatory. One can hire a guide at the gate who will tell a detail description about this yantras and avoid coming on an overcast day because all the instruments require sunlight to function. Entry fee Rs 10; Timings : 9 am to 4.30 pm.

The Small Samrat Yantra is a triangular structure consists of a large sundial marked with hours and minutes. The Samrat Yantra's gnomon is a huge triangle made of local stone and are constructed on Jaipur latitude 270 North and give Solar time. To adjust the reading to Indian standard Time (IST), between 1 minute 15 seconds to 32 minutes must be added according to the time of year and solar position. The arc at the left side will show the time from sunrise to midday and the right side will show the time from midday to sunset. By observing where the shadow is sharpest, the time is calculating. 

The Dhruva Yantra locates the position of 12 Zodiac signs and the Pole Star at night. The traditional unit of measurement is the human breath calculated to be of 6 seconds duration. Thus 4 breaths = 1 pala (24 seconds), 60 palas = 1 gati (24 minutes), 60 gatis = 1 day (24 hrs).

The Narivalya Yantra is a sundial with two dials. The first dial facing towards south, to read time when the sun is in the south hemisphere (21 September to 21 March) and the other one is at the north facing towards the north for the rest of the year. At noon the sun falls on the north-south line and the time is read in normal way. Next is Jai Singh's seat (Observer's seat). Also known as the mirror of the Heaven it is a bowl-shaped instrument over 5 meters across whose interior is divided into marble-covered surfaces. One can enter here, through the spaces between the interior surfaces.