Pragnya IAS · Map 64 · Map skills
Survey of India: reference map of topographical sheets
Decode the numbering of India’s topo sheets — the index system every geography practical uses.
STUDY NOTE 1
The million-sheet grid
India is divided into 1:1,000,000 sheets (4°×4°), numbered like 53, 54, 55; each subdivides into 1:250k (letters A–P), then 1:50k (numbers 1–16) and 1:25k sheets.
STUDY NOTE 2
Reading a number
Sheet 53J/7 identifies a specific 1:50k sheet: 53 is the million sheet, J the quarter-million division, 7 the 50k subdivision.
STUDY NOTE 3
What a topo sheet shows
Contours, drainage, settlements, roads, vegetation and symbols at standard scales — the universal base for fieldwork, planning and exams.
Map reading task
Break the sheet number 45P/12 into its three levels and describe the area each level covers.
What does this survey of india: reference map of topographical sheets lesson explain?
India is divided into 1:1,000,000 sheets (4°×4°), numbered like 53, 54, 55; each subdivides into 1:250k (letters A–P), then 1:50k (numbers 1–16) and 1:25k sheets.
UPSC map practice & Geography Optional connection
For UPSC Prelims, pair the location with its state, neighbouring relief and relevant geographic process. For GS I and Geography Optional Indian geography revision, use a simple labelled sketch to explain the relationship rather than replacing the answer with place names. These are Pragnya-authored exercises, not official UPSC previous-year questions.
References & map credits
Pragnya IAS explanations and practice are independently authored. The uploaded geography compilation informed topic selection only; its pages, illustrations, advertisements and personal watermarks are not republished. Licensed base data retain their original attribution. These lessons are educational references, not navigation, legal boundary or live hazard maps.