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Observatory that put Mount Everest in record books now lies in ruins
Bhuri Tori on a hill near Sironj in Madhya Pradesh played a central role in the Great Trigonometrical Survey that contributed to measuring Mount Everest. The observatory is now ruined, with stones pried loose and neglect mounting as authorities face preservation challenges.
Why It Matters
The site marks a pivotal moment in geodesy and cartography, illustrating how historical scientific infrastructure shaped our understanding of global geography. Its degradation raises questions about preserving scientific heritage amid modern satellite-era measurement.
Timeline
4 Events
Radhanath Sikdar computes Mount Everest's height in the 1850s
1850
Mathematician Radhanath Sikdar later computed the height of Mount Everest in the 1850s using survey data generated through the Great Trigonometrical Survey.
George Everest adopts Bhuri Tori trigonometrical station as origin of calculation
1840
Survey records indicate Colonel George Everest adopted Kalyanpur's trigonometrical station in 1840 as the 'origin of calculation' for the Great Trigonometrical Survey.
Great Trigonometrical Survey begins under William Lambton
1800
The Great Trigonometrical Survey began in the early 1800s under William Lambton, and was later expanded by George Everest, Andrew Scott Waugh and James Walker. The project mapped territories across current-day India, Pakistan, Bangladesh, Afghanistan, Myanmar and Sri Lanka using a network of triangles and baselines, unlocking distances across thousands of kilometres and transforming cartography and geodesy.
Current state of Bhuri Tori observatory site
May 10, 2026
Today, stones have been pried loose and black stone observatories lie gutted under open skies where astronomers once mapped a continent and contributed to calculating Everest's height. The site has suffered vandalism and theft, with heritage observers noting rapid deterioration and limited preservation efforts.