Tamil Nadu publishes five-volume record of historical survey stations

Tamil Nadu has documented its historic Great Trigonometrical Survey stations and released the findings in five volumes. The Department of Survey and Settlement and the Tamil Nadu State Department of Archaeology carried out the work together.

Background

Colonel William Lambton started the Great Trigonometrical Survey at St. Thomas Mount in Chennai on April 10, 1802, during British rule. The project ran for 70 years until 1871 using theodolite instruments to set up survey stations across India, including Tamil Nadu.

Preservation

The Tamil Nadu government approved a plan to find, map, and protect these stations, which fall under the Survey of India. Officials completed field surveys to record all station details, and the Director of Survey and Settlement shared the five new volumes with District Collectors and local survey offices to help protect them.

Context

Survey stations from historical mapping projects serve as permanent physical markers that help surveyors measure land accurately over long periods. Modern mapping techniques like satellite positioning often rely on these established reference points to align old maps with new digital data.