How to search for maps, plans and architectural drawings

1. Introduction

The National Archives holds an estimated six million maps, plans and architectural drawings (in this guide simply called maps). Most of these are an integral part of files, reports and other documents and are not separately described in the online Catalogue. However, the Maps and Plans Team has spent much of the past few years adding detailed descriptions of thousands of maps to the Catalogue. This work was based on the existing printed catalogues (Maps and Plans in the Public Record Office - four volumes covering the British Isles pre-1860, the Americas, Africa, and Europe and Turkey) and on card catalogues formerly in the Map and Large Document Reading Room. Many record series consisting entirely of maps are also described in the Catalogue, though usually in less detail. At present certain maps are still described only in the paper-based catalogues.

This Research Guide aims to help you to maximise the prospects of finding maps and plans relevant to your research. For a general overview of The National Archives' map holdings and how they are arranged, see the map pages on our website and related research guides.

2. Using the online Catalogue to search for maps

The Catalogue is accessible online. For general guidance on using the catalogue, click on 'Help'.

Numerous Catalogue descriptions note the existence of maps and plans in either the 'Title' field or the 'Scope and Content' field. You can use the basic search screen to find these maps.

It is important to remember, however, that many series consisting entirely of maps are described only very summarily at piece level. These summary descriptions are often limited to a place name or an Ordnance Survey sheet number. The tithe maps, for example, are listed only by tithe district name in county subseries - no detailed information about dates, scales or mapmakers is provided, and he words 'tithe' and 'map' appear only at series level. So searching for 'Peasmarsh AND map' will not find the tithe map, but searching for 'Peasmarsh' will - but it will also find all other catalogue entries containing the word 'Peasmarsh', most of which do not refer to records containing maps.

The following sections outline effective techniques for using the Catalogue to find maps and plans.

3. Search tips to find maps of a particular place

Type 'map AND [place name]' or 'plan AND [place name]'

Typing 'map AND Jersey' (without quotes) in the 'Word or phrase' box on the basic search screen will yield a set of results. To see this example, click on the thumbnail image at the bottom of this section and look at image 1.

By clicking on the number of results for a part of the Catalogue you will access detailed lists. For example, click on the '7' by MPH for details of the seven results. Such a search will lead to maps of East Jersey, West Jersey, New Jersey (in the United States) and to plans of lands owned by Lord Jersey, as well as to maps of Jersey in the Channel Islands. By clicking on 'Date range' at the top of the list, you can sort the results in chronological order.

Search by date or by department/series code

The basic search screen also allows you to restrict your search by date or to records of a particular department or in a particular series. Click on 'More examples' for further guidance.

Run several searches or a single bracketed search to find many possible keywords at the same time

To find all maps of a place may take time and involve several searches. Begin by searching for 'place AND map'. For example, 'Biggleswade AND map' leads to four hits (at the time of publication).

Not everything which modern users would naturally identify as a map is called a map. Many, especially among older records, were entitled and catalogued as 'plans': historically, the terms 'map' and 'plan' have often been used interchangeably. A second search for 'place AND plan' may lead to further hits. For example, 'Biggleswade AND plan' adds a fifth result to the four found in the previous search.

Other useful search terms at this point may include 'diagram', 'drawing', 'sketch', 'survey', 'tracing'. If you are interested in a particular building or other man-made structure, try 'section', 'cross-section', 'elevation', 'profile', 'façade' etc in conjunction with the name of the place or structure. Early maps were often called 'plats' or 'plots' (or 'platts' or 'plotts').

Instead of running three, four or more searches, you can speed up this process by combining these into a more sophisticated single search from the basic search screen. Use OR to link several terms that can describe a map and enclose the string in round brackets. Make sure that you type the place name and the linking AND outside the brackets. The order of individual search terms does not matter but any ANDs, ORs and brackets must be in the right places.

'(map OR plan OR drawing OR sketch) AND Biggleswade'

'Biggleswade AND (plan OR drawing OR map OR sketch)'

To find words containing a foreign character with a written accent (diacritic) substitute a question mark for the accented character. A search for 'fa?ade' will find both façade and facade.

Place names

Names of countries and places can change over time and have not always been expressed consistently. Entries in the Catalogue may therefore use a variety of names and spellings: some are contemporary with the records described; some were in use at the date of original cataloguing. This may have been done many years ago, so that occasionally the place name as given in the Catalogue is contemporary neither with the document nor with present-day nomenclature.

It is often a good idea to search on a number of variant forms of a place name, for example: 'Saint Petersburg', 'St Petersburg', 'Petrograd' and 'Leningrad' all refer to the same place. You can use OR to link the variant forms and run a single search. Sophisticated bracketed searches can save you a lot of time:

('Saint Petersburg' OR 'St Petersburg' OR Petrograd OR Leningrad) AND (map OR plan)

As this type of search increases the number of hits, specifying a range of dates or other restrictions may make the results more manageable.

It is also worth searching on more general terms such as 'Balkans', 'Baltic States', 'West Indies', 'East Indies', and on well-used acronyms as well as fuller forms of names such as US/USA/United States of America; USSR/Soviet Union/Union of Soviet Socialist Republics.

Move from general to particular searches

A useful strategy for finding maps described only very briefly in the catalogue is to identify a likely record series first and then try a specific search restricted to just that series. For example, to find the tithe map for Biggleswade, start with a general search for 'tithe maps'. This will find the two main series: IR 30 and IR 77. Then search for 'Biggleswade' restricting your search to IR 30 and IR 77. This will find the reference for the right tithe map: IR 30/1/5. To see this example, click on the thumbnail at the bottom of this section and look at image 2.

Find the reference for IR 30/1/5

A similar strategy is to look at a research guide to identify relevant record series. For instance, use the map web pages or research guides index page to find the research guide for Tithe records. This guide explains that the relevant series are IR 30 and IR 77.

Identify relevant hits from general searches

Alternatively, you could reverse this strategy and begin with a general search for 'Biggleswade'. This retrieves many hits grouped under department. Clicking on the number of results for IR will find the references for the tithe map, as well as references for other tithe-related records, Valuation Office records and a death duty register. When you view the catalogue description for an individual record, the descriptions and links in the 'Context' section at the top of the entry will help you decide whether the record is relevant to you.

4. Search strategies to find maps by a particular person

Retrospective conversion work to add descriptions of maps to the Catalogue has resulted in the identification of numerous mapmakers not named in previous map catalogues. In particular, note that:

Many maps in record series WO 44, WO 55, WO 78 (and maps extracted from those series to MPH 1, MPHH 1, MFQ 1 and MR 1) bear the signatures of a number of military personnel. These may include the draughtsman, the surveyor and a whole hierarchy of superior officers. The printed catalogues do not usually name more than one of these people; sometimes this may be the draughtsman, sometimes the most senior officer (practice has varied over time). Now it should be possible to trace many more maps made or at least signed by named individuals.

Many printed maps were described in very summary fashion, if at all. Retrospective conversion work has resulted in the full cataloguing for the first time of numerous 18th and 19th century printed maps, many by well-known map publishers and some not previously recorded at all.

Mapmakers' names appear under 'Scope and content', so a basic search for the mapmaker name will identify them. Names are listed in natural language order (for example, search for Aaron Arrowsmith, not Arrowsmith Aaron).

5. Finding uncatalogued maps

The most successful strategy is often to do several searches and collate the results. This can work particularly well for records of the Colonial Office (CO) and the Foreign Office (FO), which contain many maps that have not been catalogued separately.

For example, to find a map of the boundary between British Honduras (now Belize) and Guatemala, search for 'Honduras AND Guatemala AND boundary', without typing the word map. This will produce hits which include not only descriptions containing the term 'map' but also entries for volumes of original correspondence and confidential print. It is very likely that these will also contain maps and plans even though the words 'map' or 'plan' do not appear in the descriptions. Note that records in CO are often described only in terms of British territories, for which the Colonial Office was responsible. You can retrieve further relevant hits with a search for just 'Honduras AND boundary' limited to CO (omitting Guatemala).

An alternative strategy is to identify potentially relevant series, either by running an advanced search (see below) or by searching or browsing the research guides. You can then run a basic search using relevant place names (in this case 'Honduras' and 'Guatemala') restricted to your chosen series in order to identify relevant references.

It can be worth trying both of these approaches, as each may produce different results, depending on the exact search terms that you use.

6. Using an advanced search to find series consisting entirely or substantially of maps and plans

To start an advanced search from the basic search screen click on the 'Advanced search' tab. If you cannot see the Advanced search tab, click on the 'Show advanced options' button to make this tab available. For this particular search, tick the 'series' level box.

Advanced search: selecting catalogue levels

If you wish, you can limit your search to the records of a particular department, for example FO or CO. To see an example of this, click on the thumbnail image at the bottom of this section and look at image 5.

Scroll down to the 'Content and background' section and enter the keywords 'map OR plan' in the combination field for 'Title/scope and content/background' (to see an example, click on the thumbnail and scroll to image 6). This will find series where either the series title or the description in the 'Scope and content' field mentions maps. Scroll down to the bottom of the screen and click on the 'Search' button.

Advanced search: title/scope and content/background field

Alternatively, you can search on just the 'Title' field or just the 'Scope and content' field. Searching just the 'Title' field will find only series consisting entirely or mainly of maps and plans. Searching just the 'Scope and content' field will find series that are known to include significant numbers of maps and plans alongside other kinds of records.

Having identified a relevant series, you can then return to the basic search screen to run searches for places or subjects restricted to that relevant series.

7. Using an advanced search to retrieve maps noted but not described in the Catalogue

For the past two decades or so, some government departments have noted whether maps, drawings or photographs are present in files when transferring them to our custody. Not all departments have supplied this information, but when they have, this fact is mentioned in the Catalogue by a brief note in the form 'with maps', 'with photographs' etc in the 'Notes' field. These maps have not been described individually but the descriptions of the files or volumes may indicate whether it is likely that noted maps would depict the area in which you are interested.

To find such noted maps, bring up the 'Advanced search' tab and tick the box to select piece level. Type a place name (for example, 'Arabia') in the combination field for 'Title/scope and content/background' and the keyword 'map' or 'plan' (or 'map OR plan') in the 'Notes' field.

Advanced search: notes field

This search will produce a set of results at piece level. All these files and volumes contain maps but, because the maps are not separately described, none of these references can be found by a simple search involving the word 'map'. In the case of Arabia, the hits include records of the Cabinet Office (CAB) and British Rail (AN), as well as the more obvious Foreign and Commonwealth Office (FCO).

8. Doing an advanced search by map designation

A map designation is the unique identifier assigned to a printed map by its creator. Examples of these identifiers include Ordnance Survey map series numbers, Admiralty chart numbers and numbered sequences of military mapping such as IDWO and GSGS. As detailed descriptions have been transferred from our paper map catalogues to the online Catalogue, map designations have been entered into a special 'Map designation' field. Bear in mind, however, that this has been possible only when the catalogue entry describes either a single map or several duplicates of the same printed map. Note also that if an entire series or subseries consists of printed maps, map designation information may appear in the Catalogue at series or subseries level rather than at piece or item level.

To search by map designation, go to the Advanced search screen and tick at least one level for your search (for example, tick the 'piece' level). Scroll down to find the 'Map designation' box, which is under the 'Physical description' heading near the bottom of the screen.

The number in the 'Map designation' field refers to the individual map or chart. Enter the relevant chart or sheet number in its standard format (for example, 'Admiralty chart 1771' or 'IDWO 1097'). Do not include any full stops or other punctuation. Formats like 'T.S.,G.S. No. 1675' are found in some printed sources but will not work in the Catalogue; in this case the correct format would be 'TSGS 1675'.

To see an example, click on the thumbnail below and look at image 8.

The information in the 'Map designation' field refers to the particular scale and edition of Ordnance Survey mapping (for example, 'OS six-inch County Series'), not to individual sheets. Because of the restricted size of the 'Map designation' field, 'Ordnance Survey' is usually abbreviated to 'OS', For more comprehensive results, try the search twice, once using 'Ordnance Survey' as the search term and once using 'OS'. Individual Ordnance Survey sheet numbers are noted in the 'Scope and content' field, so you can find these using either a Basic or an Advanced search. Be aware that part of the sheet number is often expressed as a Roman numeral rather than an Arabic numeral.

The largest accumulation of Ordnance Survey County Series maps at The National Archives is the set of record sheet maps transferred by the Inland Revenue Valuation Office. Although these are heavily annotated with information to aid the administration of the 1910 Finance Act, the base maps are still legible. To find a particular sheet among these records using a basic search, enter the full county name and the sheet number (for example 'Surrey XXII 4') in the 'Word or phrase' box and the department code IR in the 'Department or Series code' box.

9. Doing an advanced search by map scale number

Map scales can be stated in two ways: in words (for example, '1 inch to 1 mile') and as a ratio or representative fraction (for example, '1:63,360'). As detailed descriptions have been transferred from our paper map catalogues to the online Catalogue, scales expressed as ratios have been entered into a dedicated Map scale number field. Bear in mind, however, that this has been possible only when the catalogue entry describes either a single map or several maps at the same scale. Note that where an entire series or subseries consists of printed maps, scale information may appear in the Catalogue at series or subseries level rather than at piece or item level. To search by map scale number, go to the Advanced search screen, as above. The 'Map scale number' field is immediately below the 'Map designation' field. Map scale number is a numeric field (which means that it is only allowed to contain numbers and never any text or punctuation), so enter the scale number without '1:' and without commas or spaces. For example, type '1000000' instead of '1:1,000,000'.

Scales expressed as words appear in the 'Scope and content' field, so you can find these using a basic search. If a single entry in the Catalogue describes two or more different maps at different scales, any map scale numbers will also appear under Scope and content. To find these, do a basic search for a representative fraction in traditional format (for example 1:1,000,000 or 1:63,360). As 'Scope and content' is a free-text field, not a numeric field, we have included the traditional commas, which aid legibility, when converting descriptions from the paper catalogues. However, in some older descriptions the ratio scale has been entered either with spaces instead of the commas or with no commas or spaces. For more comprehensive results, it is therefore best to try all these variations. For example, try'1:1 000 000' and '1:1000000' and '1:1,000,000'.

10. Using 'Build a query' to search for map scales

The Build a query option on the Catalogue is very useful for finding maps at a scale smaller or greater than a certain ratio or maps within a range of scales. To see examples of building a query, click on the thumbnail and look at images 9-11.

From the basic search or advanced search screen click on the tab for 'Build a query'. (You may have to click on the 'Show advanced options' button on the basic search screen to be able to access the 'Build a query' tab.) Tick at least one Catalogue level for your search, Then select 'Map scale number' from the drop-down list and click on 'Add'.

Building a query

Remember to type the scale number as a plain number without spaces or punctuation (for example'1000000', not'1:1,000,000').

You must also select an operator to make this search work. A larger scale number indicates a smaller-scale map (which shows a larger area in less detail), whereas a smaller scale number indicates a larger-scale map (which shows a smaller area in more detail). So for maps at a smaller scale than your specified number, select the symbol '>', or for maps at a larger scale than your specified number, select the symbol '<'.

To add a place name or other information to your search, select other fields from the drop-down list. Click on 'Search' for a list of results.

Building a query using Map scale number

For example, the search above will find entries on Africa at a larger scale than 1:1,000,000. The search below will find maps of Woolwich at scales between 1:2,500 and 1:10,560.

Find a map within a range of scales

It is worth saving searches of this type for future use as they may take some time to set up. Your saved searches are available from the home page of the Catalogue, so you can run them again or refine them at a later date.

11. Finding aids outside the Catalogue

Many maps which are not yet described in detail in the online Catalogue are listed in the published catalogues, or in supplementary typescript lists and card indexes. For certain record series, there are also index maps to help you find the correct sheet. These supplementary finding aids for maps are available for consultation in the Map and Large Document Reading Room at The National Archives. Please ask staff at the enquiry desk in this area if you need help locating or using any of these finding aids.

Digitised versions of the Registrar's District maps in record series RG 18 are available online from Cassini Maps.

12. Conclusion

While increasing numbers of maps and plans can be found be searching the online Catalogue using keywords, there is still no substitute for applying archival principles when researching. Your search will be more focused, more comprehensive and usually more successful if you consider which court or government department is likely to have made, used or acquired the map you are seeking. Note too that because so many maps are within files or are bound up with correspondence (and so are not individually described in any way), there is still considerable scope for making chance discoveries.