The National Archives Logo
Guide reference: Military Records Information 40
Last updated: 26 July 2007

1. Why use this guide?

Use this guide if you are looking for military maps from the Second World War. You may find it useful to look at maps alongside written records about Second World War events, strategy and operations.

2. Essential information

The Second World War maps held at The National Archives were used by the War Office and other government departments in their recordkeeping.

Many of them are annotated or show other signs of use and wear.

Most of our Second World War maps form part of operational records or other files.

We hold very few separate sets of maps from the Second World War comparable to the trench maps and other operational map series from the First World War.

Most of these records are not viewable online. To view records which are not online you will need to visit The National Archives at Kew or pay for research.

Many other archives and libraries also hold Second World War military maps. See the section on maps held elsewhere.

Most of the maps used by British land and air forces were made by the Geographical Section, General Staff (GSGS). At the time, these maps were given reference numbers starting with the letters GSGS. Other sources may refer to specific maps by these GSGS numbers. Read more about GSGS in the background information section.

The National Archives holds many GSGS maps but we do not have complete or discrete sets of GSGS mapping from the Second World War period.

3. General search tips

You can search Discovery, our catalogue, to locate some document references to maps. When searching, bear in mind that some maps are catalogued in much less detail than others. Most maps that form part of operational records or other files have not been catalogued individually.

Try searching by:

  • place name
  • the name of a battle or operation
  • the name of a regiment or other army unit
  • GSGS number

A useful tip is to include the phrase AND (map OR plan) after the other words that you are searching for.

You can use the advanced search option on our catalogue to restrict your search to specific record seriesA grouping of records held by The National Archives, based on common function or subject. mentioned in this guide. Alternatively, you can browse these seriesa grouping of records held by The National Archives, based on common function or subject.


Read the catalogue search help for more general guidance.

4. Other methods of searching

Some Second World War maps that are not yet listed in the online catalogue are noted in paper catalogues and indexed in our reading rooms at Kew:

  • the published catalogue Maps and Plans in the Public Record Office 4: Europe and Turkey (TSO, 1998)
  • card indexes arranged by place name and by military map designations (including GSGS numbers)
  • a summary catalogue available at The National Archives, with separate binders arranged by place and by subject. Try looking in the subject binders under the headings 'Military mapping' and 'Military operations'

Only a small proportion of the maps preserved among our records are listed in any of these catalogues. You may be able to find other maps by looking speculatively through files and volumes of textual records from the Second World War period.

5. Looking for maps within British Army operational records

Many war diaries include maps, often in the appendices. These maps are rarely mentioned in catalogue entries so you will need to search speculatively.

To find a map of a particular area, action or operation, try looking for:

  • the war diary of the relevant regiment or other army unit
  • the war diaries of other units known to have been in the area at the same time
  • the war diaries of  brigades, divisions and armies
  • Military Headquarters papers

For more information about these operational records and guidance on how to search, read our guide to British Army operations in the Second World War.

6. Other record series containing many military maps

Many maps appear in War Office records. Try browsing within the following record seriesA grouping of records held by The National Archives, based on common function or subject. or searching by the names of places, operations or battles.

  • WO 32 - some files include maps
  • WO 106 - some files include maps
  • WO 192 - includes plans of forts in the United Kingdom
  • WO 208 - includes maps related to the operations of foreign armies
  • WO 223 - includes maps relating to operations in France and Netherlands, and a few maps of Britain
  • WO 234 - consists of maps of Crete, Cyrenaica (including El Alamein and Tobruk) and Egypt
  • WO 252 - includes maps, plans and surveys of places in theatres of war worldwide
  • WO 401 - includes military map catalogues and indexes from the Second World War

Other record series including many military maps are:

  • ADM 234 - includes similar material to WO 252 but for naval operations
  • CAB 44 - includes working copies of maps used in the Official War Histories
  • CAB 106 - includes maps within military reports and dispatches
  • CAB 145 - consists of maps created by the Cabinet Office Historical Section for historians writing the Official War Histories
  • DEFE 2 - includes many maps relating to named operations such as Chariot, Overlord and Torch
  • HO 193 -see our guide to the Bomb Census survey. Many Bomb Census maps are annotated copies of GSGS maps
  • WORK 43 - includes some plans, such as Catterick Camp and the defences of Portsmouth

Records relating to air and sea operations also include maps, plans and charts. See our guides to Royal Air Force operations and Royal Navy operations in the Second World War for more information about these records.

7. Understanding military grid references

Many records such as war diaries, operational orders and combat reports contain grid references to locations which look like Ordnance Survey National Grid references but do not make sense when related to the National Grid.

These location references relate to a separate military grid, which was top secret during the Second World War. This grid is sometimes called the 'purple grid', because it was originally overprinted on Ordnance Survey maps in purple ink.

Use the advance search in our catalogue to search by keyword(s) within ZOS 3 or browse ZOS 3 for a set of purple grid maps covering Great Britain only.

Consult the following websites which are useful for understanding and converting military grid references:

8. Second World War maps held elsewhere

The record set of GSGS mapping (dating back to 1881) has been transferred from the Ministry of Defence Map Library to the British Library Map Library. This includes a very large amount of Second World War material.

Many other libraries and archives hold maps dating from the Second World War period. Use the COPAC catalogue to find maps in the collections of some major UK research libraries.

9. Background information: Geographical Section, General Staff (GSGS)

9.1 What was GSGS?

Geographical Section, General Staff (GSGS, also known as MI 4) operated under the Director of Military Operations and Intelligence. Its role was to supply maps to the forces, collect data on foreign survey networks, provide training, and prepare survey data for Expeditionary Force mobilisation.

GSGS was organised into small sections, each of which specialised in maps of a particular region. The War Office Map Library, which was also part of MI 4, acquired maps and cartographic intelligence data.

Senior staff members were usually Royal Engineer officers with surveying qualifications, although there were a few Royal Artillery or infantry officers. The rest of the staff were civil technical assistants and clerks, together with some Royal Engineer other ranks.

9.2 Organisational changes during the 1930s and 1940s

In 1936, the Directorate of Military Operations and Intelligence (DMO&I) began to map north-eastern France and Belgium at 1:50,000. The volume of work necessitated some being allocated to Ordnance Survey, which was then under War Office control.

In September 1939, MI 4 moved to Cheltenham. However, General Staff and the Map Library remained in London. In late 1940, the Map Depot moved to Alperton in west London and remained there throughout the war. This resulted in fragmentation of functions and records.

As early as 1919, the War Office had agreed to supply mapping for the RAF and the Air Ministry. During the Second World War the Map Section at the Air Ministry was under the technical supervision of MI 4 officers. That system was unwieldy, and was abandoned after the war. The Air Ministry Map Section then moved to Harrow and acted independently of MI4.

MI 4 at Cheltenham had limited accommodation so new accommodation for MI 4/GSGS was acquired at Eastcote in north-west London. A Distribution Section was set up to handle supplies of maps to overseas expeditions.

10. Further reading

Use our library catalogue to find a recommended book list.

Documentation about military surveying during the Second World War is available on the Defence Surveyors' Association website.

Guide reference: Military Records Information 40

Our catalogue

Search descriptions of 20 million documents from the UK central government, law courts and other national bodies.

  • Download this guide as a PDF