India Jantar Mantar | Major Monuments of India? Mukesh Sharma - October 27, 2022 0 Do You Know l Major Monuments of India? Jantar Mantar * Construction – by 1724-36 * Producer- Maharaja Jaisingh-2 * Location- New Delhi, Jaipur, Varanasi, Ujjain and Mathura * Jantar Mantar of Jaipur is the biggest sun clock * These were astronomical observatories