Tools / Defence Land Proximity

Defence Land Proximity for India

Is this plot inside or near a military zone? Check before you buy — cantonment proximity changes what you can build and whether you need NOC clearance.

Why defence land proximity matters before you buy

Military and cantonment land is the most quietly problematic category for real estate buyers in India. The restrictions are real, the NOC requirements are genuine, and the discovery — if it comes after you've committed — is costly. This tool surfaces the issue at the research stage, before it becomes a problem.

Inside a cantonment — what it actually means

India has 62 notified cantonments governed by the Cantonments Act 2006 under the Ministry of Defence. A cantonment is not just a military installation — it is a full civil-military township with its own Cantonment Board, building regulations, and land classification system. Civilian land inside a cantonment falls into one of several categories:

Bungalow Area (BA): Originally officer bungalows, now the only class legally transferable to civilians (with Cantonment Board NOC). Even here, leasehold conditions apply.
Military Lands (ML): Held by the Army in perpetuity. Cannot be purchased privately under any circumstances.
Civil Area: Normal civilian ownership, but governed by cantonment building bylaws, not the local municipal authority.

If a seller presents land inside a cantonment as freely transferable, verify the category through the Cantonment Board before proceeding.

Adjacent to a cantonment — the NOC requirement

Within 500 m of a cantonment or military installation boundary, local planning authorities impose construction controls that are separate from normal municipal rules:

Height restrictions: Typically limited to 10 m (approximately 3 floors) without NOC from the station commander or cantonment board.
NOC from defence authorities: Required for construction above the height limit, for high-mast structures (towers, hoardings), and in some states for any permanent construction.
Delay risk: NOC processing can take 3–18 months depending on the installation and state. Projects without NOC face stop-work orders.

The specific rules vary by state, cantonment board, and the nature of the installation. Always verify with the local competent authority (usually the Town and Country Planning department) for the applicable rules.

Defence land beyond cantonments

Not all military land is a cantonment. Airfields, naval bases, firing ranges, training areas, and standalone barracks are spread across India and carry similar restrictions without the formal cantonment structure. These are governed by the Defence of India Rules and require clearance from the Ministry of Defence for any commercial or civilian activity in adjacent areas.

The data coverage note

This tool uses OpenStreetMap boundaries, which are digitized from satellite imagery by volunteers. Coverage is strong in major cities and known cantonments (Pune, Wellington, Secunderabad, Jalandhar, Meerut) but incomplete for smaller or newer installations. A result showing “No Defence Zone Nearby” does not replace official verification — check the Ministry of Defence land records or approach the local station headquarters for authoritative confirmation on high-value transactions.

What the result means

The result card shows the verdict, the distance to the nearest defence polygon, and — where available — the name and type of the nearest military facility.

Inside / Outside

Whether the query geometry falls within a mapped military or cantonment polygon. “Inside” means the point or polygon centroid is within a defence boundary — it does not distinguish between different land classes within the cantonment.

Action needed: If “Inside”, verify the land class (BA vs ML) with the Cantonment Board before any transaction.

Distance to nearest zone

Straight-line distance from your plot boundary to the nearest mapped defence polygon. 0 m means inside. Anything under 500 m is the NOC zone — construction above standard height limits requires clearance from the station commander. Shown up to 10 km; beyond 10 km, no proximity concern is flagged.

Watch out: 300 m from a cantonment boundary often means a height restriction applies even for normal residential construction.

Facility type

The type of the nearest mapped defence installation — Cantonment, Airfield, Military Base, Naval Base, Barracks, Firing Range, Training Area, etc. Each type carries its own restrictions. Airfields have aviation funnel constraints. Naval bases are among the most restricted. Firing ranges have red zone exclusions.

Example: “Airfield” within 3 km means aviation height restrictions apply — typically a sloped imaginary surface that limits structure height even before you reach 500 m from the fence.

Methodology

Data source

OpenStreetMap contributors (ODbL) — defence and cantonment land boundaries digitized from satellite imagery. The dataset covers 2,741 Polygon and MultiPolygon features (LineString features — trench/fence lines — are excluded). Sourced from data/raw/defence_land_india.geojson, ingested into PostGIS as defence_areas.

Inside detection

ST_Within(query_geometry, geom) checks if the query point or polygon is fully contained within any defence polygon. For polygon inputs, the polygon geometry itself is used. For point inputs, the point coordinate is tested directly.

Proximity query

KNN index scan: ORDER BY geom <-> query_geometry LIMIT 1 returns the nearest polygon using the GIST index. Exact distance is then computed via ST_Distance(geom::geography, ...) in metres. Proximity is capped at 10 km for display purposes — beyond 10 km, no restriction is flagged.

Verdict thresholds

Inside any defence polygon → Severe — Inside Military/Defence Zone
Within 500 m → Poor — Adjacent to Defence Zone (NOC zone)
Within 2 km → Moderate — Near Defence Zone
Within 10 km → Good — No Immediate Defence Restriction
Beyond 10 km → Good — No Defence Zone Nearby

Frequently Asked Questions

Can civilians buy land inside a cantonment?

Only Bungalow Area (BA) land can be transferred to civilians, and even then it requires NOC from the Cantonment Board. Military Lands (ML) cannot be purchased by civilians under any circumstances. The land class is determined by the cantonment's official land records — your seller should be able to show you the Cantonment Board certificate. Do not rely on the title deed alone.

Does a "good" result mean I have no restrictions?

A "good" result means no military or cantonment boundary was detected within 10 km using OpenStreetMap data. OSM coverage is incomplete — smaller installations and newer facilities may not yet be mapped. For high-value land transactions near known military areas, verify with the local Station Headquarters or the Ministry of Defence's Directorate of Military Lands (DML).

What is the NOC process for construction near a cantonment?

For construction within 500 m, you typically need to apply to the Station Commander (or the Cantonment Board, if within the cantonment's civil area) with building plans. The application must show the distance from the nearest defence boundary and the proposed structure height. Processing time ranges from 3 to 18 months. Some states (notably Maharashtra and Tamil Nadu) have a standardised NOC form; others require a direct letter to the Station HQ.

Why is this based on OpenStreetMap and not government data?

The Ministry of Defence does not publish a publicly accessible geospatial dataset of all defence and cantonment land boundaries. OSM, where volunteers have digitized boundaries from satellite imagery, is currently the most comprehensive publicly available source for this information in India. The data is indicative — for regulatory certainty, always verify against official records from the Cantonment Board or Directorate of Military Lands.

What types of facilities are included?

The dataset includes: military bases, airfields, naval bases, barracks, bunkers, military offices, training areas, firing ranges, obstacle courses, radar stations, military academies, checkpoints, danger areas, and formal cantonments. Trench lines and fence lines (LinearString geometry) are excluded — only area polygons are checked.