Who prepares topographical maps of India?

Answer: (a) Survey of India

The Survey of India (1767, Dehradun) makes topographic maps.

The idea

A topographical map shows relief together with rivers, settlements and transport features. Contours join points of equal height and make slopes readable on a flat sheet. The national mapping agency has a different job from organisations studying rocks or archaeological remains.

Why the others are wrong

(c) The GSI maps geology, not topography.

(d) The ASI handles monuments.

The trap

GSI and SoI are easy to confuse.

Elimination technique

Match the product to the organisation’s job: a geological survey studies rocks and an archaeological survey studies historical remains. A general terrain-and-settlement map belongs to the national surveying agency.

Also know

Closely spaced contours indicate a steep slope; widely spaced contours indicate a gentler one. Scale 1:50,000 means one centimetre on the map represents 500 metres on the ground. Geological maps show rock units, while cadastral maps show land parcels.