UPSC: Jantar Mantar observatories by Maharaja Jai Singh II
Did you know that 18th-century India had astronomical observatories capable of measuring time and tracking celestial movements without modern technology? Built by Maharaja Sawai Jai Singh II, Jantar Mantar consists of five astronomical observatories across India. The Jaipur observatory is a UNESCO World Heritage Site and houses the world’s largest stone sundial. These remarkable structures reflect India’s rich scientific heritage and are important for UPSC preparation. Apart from Delhi and Jaipur, in which other three cities were Jantar Mantar observatories built?

Kisalay Karn Singh · 7d ago
Ujjain, Varanasi and Mathura. The mathura one does not exist now as it was demolished in 1857 rebellion.
Gargi · 7d ago
@kks-0606 correct 💯
Gaurav Singh · 7d ago
No i didn't know
Gargi · 7d ago
@bihariaspirant kisalay wrote the answer
Dhruv Yaduvanshi · 7d ago
Jaipur’s Jantar Mantar is really nice … Maharaja Sawai Jai Singh was really a visionary person who established the city of Jaipur as well in 1727 . He was also regarded as most outstanding ruler of 18th century .
Gargi · 7d ago
@Ydhruv-6 kabhi mauka mila to jarur dekhnge
RAMAKRISHNA · 7d ago
One of the remarkable aspects of Jai Singh’s observatories is that each site is distinctly different in size, layout, and style. While the instruments he designed are essentially the same in principle, the versions at different sites vary in size, materials, and construction. The first observatory to be built was the observatory at Delhi in 1724. The Jaipur observatory, the most elaborate, was begun by 1728. Smaller observatories were built in Benares, Ujjain, and Mathura. Of the five observatories, all except the observatory at Mathura still exist and are publicly accessible. The Mathura observatory, and the fort in which it was housed, were demolished just before 1857. The observatories at Delhi and Jaipur are the best known and most visited, since they are within major tourist destinations. They also feature the largest versions of the instruments Jai Singh built, and the Jaipur observatory houses the greatest number and variety of instruments.
Gargi · 7d ago
@aspirant-8406 Thanks for sharing this 🙏