Where does this come from, and can I check it?

Chains of triangles across the subcontinent fixed distances and heights to a few inches. The figure is taken from Survey of India, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a history fact?

Yes. It sits on the History shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

The Great Trigonometrical Survey measured all of India

Chains of triangles across the subcontinent fixed distances and heights to a few inches Begun in 1802, the survey used theodolites to measure a chain of triangles from the southern tip of India northward, taking seventy years to finish. It produced the first accurate map of the subcontinent and measured Himalayan peaks, including the mountain then called Peak XV. It also gave the world a standard for geodesy. It sits in Mondo's history collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Survey of India

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: surveying, india, cartography

The Great Trigonometrical Survey measured all of India: the short answers

Where does this come from, and can I check it?: Chains of triangles across the subcontinent fixed distances and heights to a few inches. The figure is taken from Survey of India, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a history fact?: Yes. It sits on the History shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.