Survey of India

The Survey of India (Hindi: भारतीय सर्वेक्षण विभाग) is India's central engineering agency in charge of mapping and surveying. Set up in 1767 to help consolidate the territories of the British East India Company, it is one of the oldest Engineering Departments of the Government of India. The Survey of India's distinguished history includes the handling of the mammoth Great Trigonometrical Survey under William Lambton and George Everest and the discovery of Mt. Everest. Its members are from Survey of India Service cadre of Civil Services of India. It is headed by the Surveyor General of India.

Survey of India publishes maps and the unrestricted category maps can be obtained at very reasonable prices from its several Geo-spatial data centers. Restricted category maps require due approval from government authorities. Many other rules govern the sale and use of Survey of India maps. Only an Indian citizen may purchase topographic maps and these may not be exported from India for any reason.

The history of the Survey of India dates back to the 18th Century.

A) First Survey in India Baramahal : the present Dharmapuri, Krishnagiri and North Arcot were called as baramahal. Col. Alexander Read Superintendent of Salem and Baramahal ordered for Socio Economic Survey of Salem and Dharmapuri District was started by January,1793 under the Head of W.Mather and completed by the year 1796. [Reference : Baramahal records Vol.I P.220] In Letter Dated 04.10.1797 the British Government appreciated Col. Alexander Read.

B) The Great Trigonometry Survey

The Great Trigonometry Survey was started by British surveyor Col. William Lambton on the 10th of April 1802. It was started from St.Thomas Mount, Chennai to foothills of Himalayas. It took 57 days to measure the 12-km base line. 36 inch huge ½ ton weight Theodolite was used to measure. This 5-decade project was completed under Survey General Lt George Everest in the year 1852. Surveyor Radhanath Sikdar measured Mount Everest in 1852, with a height of 29,002 feet. Modern measurements indicate the height is 29,037 feet. This is regarded as the beginning of systematic topographical mapping in India and the founding of one of the oldest survey and mapping agencies in the world.

...
Wikipedia