Jantar Mantar is a stone built architecture that measure the time of day. There were five Jantar Mantars in India located at Jaipur, Mathura, New Delhi, Ujjain and Varanasi.
Jantar Mantar of Jaipur was built by the Rajput king Sawai Jai Singh II, A UNESCO World Heritage site in Jaipur that also features the world’s largest stone sundial. The monument is located near City Palace, Hawa Mahal and a must see place of the city.
Jantar Mantar in New Delhi consists of 13 architectural astronomy instruments and there are 4 distinct instruments within the observatory called Samrat Yantra, Jayaprakash, Rama Yantra and Misra Yantra.
Jantar Mantar of Varanasi is a must see place of the city and one of the five built by Maharaja Jai Singh II. The Jantar Mantar is constructed to measure declination of Sun, stars and planets.
Jantar Mantar is another observatory built by Maharaja Jai Singh II that also consists of 13 architectural astronomy instruments. Vedh Shala of Ujjain or Jantar Mantar measure declination of the Sun, stars and planets.
Mathura Jantar Mantar is one of the five observatories built by the Maharaja Jai Singh in same monarch in northern India. There are 16 devices at Jantar Mantar, designated to measure time and to study in similar observatories.