Ordnance Survey (OS) is a national mapping agency in the United
Kingdom which covers the island of Great Britain. It is one of the
world's largest producers of maps. Since 1 April 2015 it has operated
Ordnance Survey Ltd, a government-owned company, 100% in public
Ordnance Survey Board remains accountable to the
Secretary of State for Business, Energy and Industrial Strategy. It is
also a member of the Public Data Group.
The agency's name indicates its original military purpose (see
ordnance and surveying), which was to map
Scotland in the wake of the
Jacobite rising of 1745. There was also a more general and nationwide
need in light of the potential threat of invasion during the
Ordnance Survey mapping is usually classified as either "large-scale"
(in other words, more detailed) or "small-scale". The Survey's
large-scale mapping comprises 1:2,500 maps for urban areas and
1:10,000 more generally. (The latter superseded the 1:10,560 "six
inches to the mile" scale in the 1950s.) These large scale maps are
typically used in professional land-use contexts and were available as
sheets until the 1980s, when they were digitised. Small-scale mapping
for leisure use includes the 1:25,000 "Explorer" series, the 1:50,000
"Landranger" series and the 1:250,000 road maps. These are still
available in traditional sheet form.
Ordnance Survey maps remain in copyright for fifty years after their
publication. Some of the
Copyright Libraries hold complete or
near-complete collections of pre-digital OS mapping.
2 Great Britain "County Series"
3 City and town mapping, 19th and early 20th century
4 20th century
5 21st century
6 GB map range
6.1 Business mapping
6.2 Leisure maps
6.3 App development
6.4 Custom products
6.5 Educational mapping
6.6 Derivative and licensed products
8 OS MasterMap
8.1 OS Master
9 Geographical information science research
10 Data access and criticisms
10.1 OS OpenData
10.2 Historical material
11 See also
14 External links
The origins of the
Ordnance Survey lie in the aftermath of the
Jacobite rising of 1745
Jacobite rising of 1745 which was finally defeated by forces loyal to
the government at the
Battle of Culloden
Battle of Culloden in 1746. Prince William, Duke
of Cumberland realised that the British Army did not have a good map
Scottish Highlands to locate Jacobite dissenters such as Simon
Fraser, 11th Lord Lovat so that they could be put on trial. In
1747, Lieutenant-Colonel David Watson proposed the compilation of a
map of the Highlands to help to subjugate the clans. In response,
King George II charged Watson with making a military survey of the
Highlands under the command of the Duke of Cumberland. Among Watson's
assistants were William Roy,
Paul Sandby and John Manson. The survey
was produced at a scale of 1 inch to 1000 yards (1:36,000) and
included "the Duke of Cumberland's Map" (primarily by Watson and Roy),
now held in the British Library.
Roy later had an illustrious career in the
Royal Engineers (RE),
rising to the rank of General, and he was largely responsible for the
British share of the work in determining the relative positions of the
French and British royal observatories. This work was the starting
point of the
Principal Triangulation of Great Britain
Principal Triangulation of Great Britain (1783–1853),
and led to the creation of the
Ordnance Survey itself. Roy's technical
skills and leadership set the high standard for which Ordnance Survey
became known. Work was begun in earnest in 1790 under Roy's
supervision, when the
Board of Ordnance
Board of Ordnance (a predecessor of part of the
modern Ministry of Defence) began a national military survey starting
with the south coast of England. Roy's birthplace near
South Lanarkshire is today marked by a memorial in the form of a large
OS trig point.
By 1791 the Board received the newer
Ramsden theodolite (an improved
successor to the one that Roy had used in 1784), and work began on
mapping southern Great Britain using a five-mile baseline on Hounslow
Heath that Roy himself had previously measured; it crosses the present
Heathrow Airport. In 1991
Royal Mail marked the bicentenary by issuing
a set of postage stamps featuring maps of the Kentish village of
In 1801 the first one-inch-to-the-mile (1:63,360 scale) map was
published, detailing the county of Kent, with
Essex following shortly
Kent map was published privately and stopped at the
county border, while the
Essex maps were published by Ordnance Survey
and ignore the county border, setting the trend for future Ordnance
The original draftsman's drawings for the area around St Columb Major
in Cornwall, made in 1810
In the next 20 years about a third of England and
Wales was mapped at
the same scale (see Principal
Triangulation of Great Britain) under
the direction of William Mudge, as other military matters took
precedence. It took until 1823 to re-establish a relationship with the
French survey made by Roy in 1787. By 1810 one inch to the mile maps
of most of the south of England were completed, but they were
withdrawn from sale between 1811 and 1816 because of security
fears. By 1840 the one-inch survey had covered all of
Wales and all
but the six northernmost counties of England.
It was hard work: Major Thomas Colby, the longest-serving Director
General of Ordnance Survey, walked 586 miles (943 km) in 22 days
on a reconnaissance in 1819. In 1824, Colby and most of his staff
moved to Ireland to work on a six-inches-to-the-mile (1:10,560)
valuation survey. The survey of Ireland, county by county, was
completed in 1846. The suspicions and tensions it caused in rural
Ireland are the subject of Brian Friel's play Translations.
Colby was not only involved in the design of specialist measuring
equipment. He also established a systematic collection of place names,
and reorganised the map-making process to produce clear, accurate
plans. Place names were recorded in "Name Books", a system
first used in Ireland. The instructions for their use were:
"The persons employed on the survey are to endeavour to obtain the
correct orthography of the names of places by diligently consulting
the best authorities within their reach. The name of each place is to
be inserted as it is commonly spelt, in the first column of the name
book and the various modes of spelling it used in books, writings
&c. are to be inserted in the second column, with the authority
placed in the third column opposite to each."
Whilst these procedures generally produced excellent results, mistakes
were made: for instance, the Pilgrims Way in the
North Downs labelled
the wrong route, but the name stuck. Similarly, the spelling of
Scafell Pike copied an error on an earlier map, and
was retained as this was the name of a corner of one of the Principal
Triangles, despite "Scawfell" being the almost universal form at the
Colby believed in leading from the front, travelling with his men,
helping to build camps and, as each survey session drew to a close,
arranging mountain-top parties with enormous plum puddings.
The old site of Ordnance Survey, London Road,
Southampton City Centre,
British Geological Survey
British Geological Survey was founded in 1835 as the Ordnance
Geological Survey under Henry De la Beche, and remained a branch of
Ordnance Survey until 1965. At the same time the uneven quality of
the English and Scottish maps was being improved by engravers under
Benjamin Baker. By the time Colby retired in 1846, the production of
six-inch maps of Ireland was complete. This had led to a demand for
similar treatment in England, and work was proceeding on extending the
six-inch map to northern England, but only a three-inch scale for most
When Colby retired he recommended
William Yolland as his successor,
but he was considered too young and the less experienced Lewis
Alexander Hall was appointed. After a fire in the Tower of London,
the headquarters of the survey was moved to Southampton, and Yolland
was put in charge, but Hall sent him off to Ireland so that when Hall
left in 1854 Yolland was again passed over in favour of Major Henry
James. Hall was enthusiastic about extending the survey of the north
of England to a scale of 1:2,500. In 1855, the
Board of Ordnance
Board of Ordnance was
abolished and the
Ordnance Survey was placed under the War Office
together with the Topographical Survey and the Depot of Military
Knowledge. Eventually in 1870 it was transferred to the Office of
The primary triangulation of the United Kingdom of Roy, Mudge and
Yolland was completed by 1841, but was greatly improved by Alexander
Ross Clarke who completed a new survey based on Airy's spheroid in
1858, completing the Principal Triangulation. The following year,
he completed an initial levelling of the country.
Great Britain "County Series"
Scan of the cover of the 5th series OS map Chelmsford and Southend
sheet 108. Art by Ellis Martin
Ordnance Survey published its first large-scale maps of
Ireland in the mid-1830s, the
Tithe Commutation Act 1836
Tithe Commutation Act 1836 led to calls
for a similar six-inch to the mile survey in England and Wales.
Official procrastination followed, but the development of the railways
added to pressure that resulted in the
Ordnance Survey Act 1841. This
granted a right to enter property for the purpose of the survey.
Following a fire at its headquarters at the
Tower of London
Tower of London in
Ordnance Survey relocated to a site in
was in disarray for several years, with arguments about which scales
to use. Major-General Sir Henry James was by then Director General,
and he saw how photography could be used to make maps of various
scales cheaply and easily. He developed and exploited
photozincography, not only to reduce the costs of map production but
also to publish facsimiles of nationally important manuscripts.
Between 1861 and 1864, a facsimile of the
Domesday Book was issued,
county by county; and a facsimile of the Gough
Map was issued in 1870.
From the 1840s, the
Ordnance Survey concentrated on the Great Britain
"County Series", modelled on the earlier Ireland survey. A start was
made on mapping the whole country, county by county, at six inches to
the mile (1:10,560). From 1854, to meet requirements for greater
detail, including land-parcel numbers in rural areas and accompanying
information, cultivated and inhabited areas were mapped at 1:2500
(25.344 inches to the mile), at first parish by parish, with
blank space beyond the parish boundary, and later continuously.
Early copies of 1:2500 maps were available hand-coloured. Up to 1879
the 1:2500 maps were accompanied by Books of Reference or "area books"
that gave acreages and land-use information for land-parcel numbers.
After 1879, land-use information was dropped from these area books;
after the mid-1880s, the books themselves were dropped and acreages
were printed instead on the maps. After 1854, the six-inch maps
and their revisions were based on the "twenty-five inch" maps and
theirs.[clarification needed] The six-inch sheets covered an area of
six by four miles on the ground; the "twenty-five inch" sheets an area
of one by one and a half. One square inch on the "twenty-five inch"
maps was roughly equal to an acre on the ground. In later editions the
six-inch sheets were published in "quarters" (NW, NE, SW, SE), each
covering an area of three by two miles on the ground. The first
edition of the two scales was completed by the 1890s. A second edition
(or "first revision") was begun in 1891 and completed just before the
First World War. From 1907 till the early 1940s, a third edition (or
"second revision") was begun but never completed: only areas with
significant changes on the ground were revised, many two or three
times. Publication of the one-inch to the mile series for
Great Britain was completed in 1891.
From the late 19th century to the early 1940s, the OS produced many
"restricted" versions of the County Series maps and other War
Department sheets for
War Office purposes, in a variety of large
scales that included details of military significance such as
dockyards, naval installations, fortifications and military camps.
Apart from a brief period during the disarmament talks of the 1930s,
these areas were left blank or incomplete on standard maps. The War
Department 1:2500s, unlike the standard issue, were contoured. The
de-classified sheets have now been deposited in some of the Copyright
Libraries, helping to complete the map-picture of pre-Second World War
City and town mapping, 19th and early 20th century
From 1824, the OS began a 6 inch (1:10,560) survey of Ireland for
taxation purposes but found this to be inadequate for urban areas and
adopted the five-foot scale (1:1056) for Irish cities and towns.
From 1840, the six-inch standard was adopted in Great Britain for the
un-surveyed northern counties and the 1:1056 scale also began to be
adopted for urban surveys. Between 1842 and 1895, some 400 towns
were mapped at 1:500 (126 inches), 1:528 (120 inches, "10 foot scale")
or 1:1056 (60 inches), with the remaining towns mapped at 1:2500 (~25
inches). In 1855, the Treasury authorised funding for 1:2500 for
rural areas and 1:500 for urban areas. The 1:500 scale was
considered more 'rational' than 1:528 and became known as the
"sanitary scale" since its primary purpose was to support
establishment of mains sewerage and water supply. However, a
review of the
Ordnance Survey in 1892 found that sales of the 1:500
series maps were very poor and the Treasury declined to fund their
continuing maintenance, declaring that any revision or new mapping at
this scale must be self-financing. Very few towns and cities saw a
second edition of the town plans: by 1909 only fourteen places had
paid for updates. The review determined that revision of 1:2500
mapping should proceed apace.
The most detailed mapping of London was the OS's 1:1056 survey between
1862 and 1872, which took 326 sheets to cover the capital; a
second edition (that needed 759 sheets due to urban expansion) was
completed and brought out between 1891 and 1895. London was
unusual in that land registration on transfer of title was made
compulsory there in 1900. The 1:1056 sheets were partially revised
to provide a basis for
HM Land Registry
HM Land Registry index maps and the OS mapped
the whole London County Council area (at 1:1056) at national
From 1911 onwards – and mainly between 1911 and 1913 –
Ordnance Survey photo-enlarged many 1:2500 sheets covering
built-up areas to 1:1250 (50.688 inches to the mile) for Land
Valuation and Inland Revenue purposes: the increased scale was to
provide space for annotations. About a quarter of these 1:1250s
were marked "Partially revised 1912/13". In areas where there were no
further 1:2500s, these partially revised "fifty inch" sheets represent
the last large-scale revision (larger than six-inch) of the County
Series. The County Series mapping was superseded by the Ordnance
Survey National Grid 1:1250s, 1:2500s and 1:10,560s after the Second
Front cover of a one-inch to the mile New Popular Edition, from 1945
Detailed scan of a complete 7th series sheet
During World War I, the
Ordnance Survey was involved in preparing maps
of France and Belgium. During World War II, many more maps were
1:40,000 map of Antwerp, Belgium
1:100,000 map of Brussels, Belgium
1:5,000,000 map of South Africa
1:250,000 map of Italy
1:50,000 map of north-east France
1:30,000 map of the Netherlands with manuscript outline of districts
occupied by the German Army.
After the war, Colonel Charles Close, then Director General, developed
a strategy using covers designed by Ellis Martin to increase sales in
the leisure market. In 1920
O. G. S. Crawford
O. G. S. Crawford was appointed
Archaeology Officer and played a prominent role in developing the use
of aerial photography to deepen understanding of archaeology.
In 1935, the Davidson Committee was established to review the Ordnance
Survey's future. The new Director General, Major-General Malcolm
MacLeod, started the retriangulation of Great Britain, an immense task
involving the erection of concrete triangulation pillars ("trig
points") on prominent hilltops as infallible positions for
theodolites. Each measurement made by theodolite during the
retriangulation was repeated no fewer than 32 times.
The Davidson Committee's final report set the
Ordnance Survey on
course for the 20th century. The metric national grid reference system
was launched and a 1:25000-scale series of maps was introduced. The
one-inch maps continued to be produced until the 1970s, when they were
superseded by the 1:50000-scale series – as proposed by William
Roy more than two centuries earlier.
Ordnance Survey had outgrown its site in the centre of Southampton
(made worse by the bomb damage of the Second World War). The bombing
during the Blitz devastated
Southampton in November 1940 and destroyed
most of Ordnance Survey's city centre offices. Staff were
dispersed to other buildings and to temporary accommodation at
Chessington and Esher, Surrey, where they produced 1:25000 scale maps
of France, Italy, Germany and most of the rest of Europe in
preparation for its invasion. Until 1969,
Ordnance Survey largely
remained at its
Southampton city centre HQ and at temporary buildings
in the suburb of
Maybush nearby, when a new purpose-built headquarters
was opened in
Maybush adjacent to the wartime temporary buildings
there. Some of the remaining buildings of the original Southampton
city-centre site are now used as part of the city's court complex.
The new head office building was designed by the Ministry of Public
Buildings and Works for 4000 staff, including many new recruits who
were taken on in the late 1960s and early 70s as draughtsmen and
surveyors. The buildings originally contained
factory-floor space for photographic processes such as
heliozincography and map printing, as well as large buildings for
storing flat maps. Above the industrial areas are extensive office
areas. The complex is notable for its concrete mural by sculptor Keith
McCarter and the concrete elliptical paraboloid shell roof over the
staff restaurant building.
Ordnance Survey digitised the last of about 230,000 maps,
making the United Kingdom the first country in the world to complete a
programme of large-scale electronic mapping. In 1999 the agency
was designated a Trading Fund, required to cover its costs by charging
for its products and to remit a proportion of its profits to the
Treasury. Officially, it is now a civilian organisation with executive
agency status.
By the late 1990s technological developments had eliminated the need
for vast areas for storing maps and for making printing plates by
hand. Although there was a small computer section at Ordnance Survey
in the 1960s, the digitising programme had replaced the need for
printing large-scale maps, while computer-to-plate technology (in the
form of a single machine) had also rendered the photographic
platemaking areas obsolete. Part of the latter was converted into a
new conference centre in 2000, which was used for internal events and
also made available for external organisations to hire.
Ordnance Survey headquarters in Maybush, Southampton, used from
1969 until 2011
Headquarters in Adanac Park opened in 2011
In summer 2010 OS announced that printing and warehouse operations
were to be outsourced, ending over 200 years of in-house
printing. The Frome-based firm Butler, Tanner and Dennis
(BT&D) secured its printing contract. As already stated,
large-scale maps had not been printed at
Ordnance Survey since the
common availability of geographical information systems (GISs), but,
until late 2010, the OS Explorer and OS Landranger series were printed
In April 2009 building began of a new head office in Adanac Park on
the outskirts of Southampton.
By 10 February 2011 virtually all staff had relocated to the new
"Explorer House" building and the old site had been sold off and
redeveloped. Prince Philip officially opened the new headquarters
building on 4 October 2011.
On 22 January 2015 plans were announced for the organisation to move
Trading Fund model to a government-owned limited company, with
the move completed in April 2015. The organisation remains fully owned
by the UK government and retains many of the features of a public
On 6 March 2015 a new
CEO was announced to replace Vanessa Lawrence,
who had left in 2014. Nigel Clifford,
CEO of Procserve Holdings Ltd,
was appointed by Business Minister Matthew Hancock.
In September 2015 the history of the
Ordnance Survey was the subject
BBC Four TV documentary entitled A Very British Map: The Ordnance
GB map range
Ordnance Survey produces a large range of paper maps and digital
Ordnance Survey produces a wide variety of different products aimed at
business users, such as utility companies and local authorities. The
data is supplied by
Ordnance Survey on optical media or increasingly,
via the Internet. Products can be downloaded via FTP or accessed 'on
demand' via a web browser. Organisations using
Ordnance Survey data
have to purchase a licence to do so. Some of the main products are:
(see below) Ordnance Survey's most detailed mapping showing individual
buildings and other features in a vector format. Every real-world
object is assigned a unique reference number (TOID) that allows
customers to add this reference to their own databases. OS MasterMap
consists of several so-called "layers" (see below) such as the aerial
imagery, transport and postcode. The principal layer is the
A customisable vector product at 1:10,000 scale.
a raster map at 1:10 000 scale.
Meridian 2, Strategi
Mid-scale mapping in vector format.
A joint venture with
Royal Mail producing datasets with address
information to allow postcode searches, etc.
Mapping showing administrative boundaries such as counties, parishes
and electoral wards.
10,000, 1:25,000, 1:50,000, 1:250,000 scale raster : Raster
versions of leisure maps.
OS Street View
A highly simplified mapping focusing on streets and their names at the
expense of other features.
Land-Form PROFILE, PROFILE Plus, Panorama
Digital terrain models.
Illustration of the
Ordnance Survey National Grid
Ordnance Survey National Grid coordinate system,
with Trafalgar Square as an example
OS's range of leisure maps are published in a variety of scales:
Tour (c. 1:100,000, except Scotland)
One-sheet maps covering a generally county-sized area, showing major
and most minor roads and containing tourist information and selected
footpaths. Tour maps are generally produced from enlargements of
1:250,000 mapping. Several larger scale town maps are provided on each
sheet for major settlement centres. The maps have sky-blue covers and
there are eight sheets in the series.
OS Landranger (1:50,000)
The "general purpose" map. They have pink covers; 204 sheets cover the
whole of Great Britain and the Isle of Man. The map shows all
footpaths and the format is similar to the Explorer maps, but with
OS Landranger Active (1:50,000)
Select OS Landranger maps available in a plastic-laminated waterproof
version, similar to the OS Explorer Active range. As of
October 2009[update], 25 of the 204 Landranger maps were
available as OS Landranger Active maps.
OS Explorer, (1:25,000)
Specifically designed for walkers and cyclists. They have orange
covers, and contain 403 sheets covering the whole of Great Britain
Isle of Man
Isle of Man is excluded from this series). These are the most
detailed leisure maps that
Ordnance Survey publish and cover all types
of footpaths and most details of the countryside for easy navigation.
The OL branded sheets within the Explorer series show areas of greater
interest in England and
Wales (such as the Lake District, the Black
Mountains, etc.) with an enlarged area coverage. They appear identical
to the ordinary Explorer maps, except for the numbering and a little
yellow mark on the corner (a relic of the old Outdoor Leisure series).
The OS Explorer maps, together with the former Outdoor Leisure series,
superseded the numerous green-covered Pathfinder maps. In May 2015
Ordnance Survey announced that the new release of OL series maps would
come with a mobile download version, available through a dedicated app
on Android and iOS devices. It is expected that this will be
rolled out to all the Explorer and Landranger series over time.
OS Explorer Active (1:25,000 scale)
OS Explorer and Outdoor Leisure maps in a plastic-laminated waterproof
An experimental range of maps designed to support specific activities.
The four map packs currently published are Off-Road Cycling Hampshire
North, South, East and West. Each map pack contains 12 cycle routes
printed on individual map sheets on waterproof paper. While they are
based on the 1:25,000 scale maps, the scales have been adjusted so
each route fits on a single A4 sheet.
Until 2010, OS also produced the following:
A double-sided map designed for long-distance road users, covering the
whole of Great Britain.
A series of eight sheets covering Great Britain, designed for road
These, along with fifteen Tour maps, were discontinued during January
2010 as part of a drive for cost-efficiency.
The Road series was reintroduced in September 2016.
Ordnance Survey released its first official app, OS
MapFinder, and has since added three more apps.
Available on iOS and Android, the free to download app allows users to
access maps direct to their devices, plan and record routes and share
routes with others. Users can subscribe and download OS Landranger and
OS Explorer high-resolution maps in 660dpi quality and use them
without incurring roaming charges as maps are stored on the device and
can be used offline – without WiFi or mobile signal.
OS Maps Web
Available as a web page – it allows users to access maps from the
web using modern web browsers, planning of custom routes and printing
of maps is possible similarly to what the mobile applications can do
Launched in February 2014 and available on iOS and Android, the free
app is a fast and highly accurate means of pinpointing a users exact
location and displays grid reference, latitude, longitude and
altitude. OS Locate does not need a mobile signal to function, so the
inbuilt GPS system in a device can be relied upon.
Launched in 2014 on iOS, the free app uses Ordnance Survey's detailed
outdoor mapping including OS Landranger Maps (1:50 000 scale) enabling
cyclists to successfully navigate and track their progress as they
ride the pre-loaded routes and follow in the tracks of the 2014 Grand
Depart professional cyclists.
Ordnance Survey also offers OS Custom Made, a print-on-demand service
based on digital raster data that allows a customer to specify the
area of the map or maps desired. Two scales are offered –
1:50,000 (equivalent to 40 km by 40 km) or 1:25,000
(20 km by 20 km) – and the maps may be produced
either folded or flat for framing or wall mounting. Customers may
provide their own titles and cover images for folded maps.
Ordnance Survey also produces more detailed custom mapping to order,
at 1:10,000 (Landplan) and at 1:1,250 or 1:500 (Siteplan), from its
large-scale digital data. Custom scales may also be produced from the
enlargement or reduction of the existing scales.
Ordnance Survey supplies reproductions of its maps from the early
1970s to the 1990s for educational use. These are widely seen in
schools both in Britain and in former British colonies, either as
stand-alone geographic aids or as part of geography textbooks or
During the 2000s, in an attempt to increase schoolchildren's awareness
Ordnance Survey offered a free OS Explorer
Map to every
11-year-old in UK primary education. By the end of 2010, when the
scheme closed, over 6 million maps had been given away. The scheme
was replaced by free access to the
Digimap for Schools service
EDINA for eligible schools.
With the trend away from paper products towards geographical
information systems (GISs),
Ordnance Survey has been looking into ways
of ensuring schoolchildren are made aware of the benefits of GISs and
has launched "MapZone", an interactive child-orientated website
featuring learning resources and map-related games.
Ordnance Survey publishes a quarterly journal, principally for
geography teachers, called Mapping News.
Derivative and licensed products
One series of historic maps, published by Cassini Publishing Ltd, is a
reprint of the
Ordnance Survey first series from the mid-19th century
but using the OS Landranger projection at 1:50,000 and given 1 km
gridlines. This means that features from over 150 years ago fit almost
exactly over their modern equivalents and modern grid references can
be given to old features.
The digitisation of the data has allowed
Ordnance Survey to sell maps
electronically. Several companies are now licensed to produce the
popular scales (1:50,000 and 1:25,000) and their own derived datasets
of the map on CD/DVD or to make them available online for download.
The buyer typically has the right to view the maps on a PC, a laptop,
and a pocket PC/smartphone, and to print off any number of copies. The
accompanying software is GPS-aware, and the maps are ready-calibrated.
Thus, the user can quickly transfer the desired area from their PC to
their laptop or smartphone, and go for a drive or walk with their
position continually pinpointed on the screen. The individual map is
more expensive than the equivalent paper version, but the price per
square km falls rapidly with the size of coverage bought.
Ordnance Survey maps of Great Britain use the Ordnance Survey
Ordnance Survey National Grid
The Ordnance Survey's original maps were made by triangulation. For
the second survey, in 1934, this process was used again and resulted
in the building of many triangulation pillars (trig points): short (c.
4 feet/1.2 m high), usually square, concrete or stone pillars at
prominent locations such as hill tops. Their precise locations were
determined by triangulation, and the details in between were then
filled in with less precise methods.
Ordnance Survey maps are largely based on aerial photographs,
but large numbers of the pillars remain, many of them adopted by
private land owners.
Ordnance Survey still has a team of surveyors
across Great Britain who visit in person and survey areas that cannot
be surveyed using photogrammetric methods (such as land obscured by
vegetation) and there is an aim of ensuring that any major feature
(such as a new motorway or large housing development) is surveyed
within six months of being built. While original survey methods were
largely manual, the current surveying task is simplified by the use of
GPS technology, allowing the most precise surveying standards yet.
Ordnance Survey is responsible for a UK-wide network of GPS stations
known as "OS Net". These are used for surveying and other
organisations can purchase the right to utilise the network for their
Ordnance Survey still maintains a set of master geodetic reference
points to tie the
Ordnance Survey geographic datum points to modern
measurement systems such as GPS.
Ordnance Survey maps of Great Britain
Ordnance Survey National Grid
Ordnance Survey National Grid rather than latitude and
longitude to indicate position. The Grid is known technically as
Ordnance Survey Great Britain 1936) and was introduced after
the 1936–1953 retriangulation.
Whereas cartography is the art and science of mapmaking, cartographic
design concerns the map user. It governs the design of a map and it is
the cartography that ensures the intended message is delivered both
efficiently and aesthetically.[clarification needed]
Ordnance Survey's CartoDesign team performs a key role in the
organisation, as the authority for cartographic design and
development, and engages with internal and external audiences to
promote and communicate the value of cartography. They work on a broad
range of projects and are responsible for styling all new products and
Ordnance Survey's flagship digital product, launched in November 2001,
is OS MasterMap, a database that records, in one continuous digital
map, every fixed feature of Great Britain larger than a few metres.
Every feature is given a unique
TOID (TOpographical IDentifier), a
simple identifier that includes no semantic information. Typically,
TOID is associated with a polygon that represents the area on the
ground that the feature covers, in National Grid coordinates.
Map is offered in themed layers, each linked to a number of
TOIDs. As of September 2010, the layers are:
The primary layer of OS MasterMap, consisting of vector data
comprising large-scale representation of features in the real world,
such as buildings and areas of vegetation. The features captured and
the way they are depicted is listed in a specification available on
Ordnance Survey website.
Integrated transport network
A link-and-node network of transport features such as roads and
railways. This data is at the heart of many satnav systems. In an
attempt to reduce the number of HGVs using unsuitable roads, a
data-capture programme of "Road Routing Information" was
recently[when?] undertaken, aiming to add information such as height
restrictions and one-way streets.
Orthorectified aerial photography in raster format.
An overlay adding every address in the UK to other layers.
Adds further information to the Address layer, such as addresses with
multiple occupants (blocks of flats, student houses, etc.) and objects
with no postal addresses, such as fields and electricity substations.
Pricing of licenses to OS Master
Map data depends on the total area
requested, the layers licensed, the number of TOIDs in the layers, and
the period in years of the data usage. OS Master
Map can be used to
generate maps for a vast array of purposes and maps can be printed
from OS Master
Map data with detail equivalent to a traditional 1:1250
scale paper map.
Ordnance Survey states that thanks to continuous review, OS MasterMap
data is never more than six months out of date. The scale and detail
of this mapping project is unique. By 2009, around
440 million TOIDs had been assigned, and the database stood at 600
gigabytes in size. Currently (March 2011), OS claims 450 million
TOIDs. As of 2005, OS Master
Map was at version 6; 2010's version 8
includes provision for Urban Paths (an extension of the "integrated
transport network" layer) and pre-build address layer. All these
versions have a similar GML schema.
Geographical information science research
For several decades
Ordnance Survey has had a research department that
is active in several areas of geographical information science,
Spatial data modelling
Remote sensing and analysis of remotely sensed data
Semantics and ontologies
Ordnance Survey actively supports the academic research community
through its external research and university liaison team. The
research department actively supports MSc and PhD students as well as
engaging in collaborative research. Most
Ordnance Survey products are
available to UK universities that have signed up to the Digimap
agreement and data is also made available for research purposes that
advances Ordnance Survey's own research agenda.
More information can be found at
Ordnance Survey Research.
Data access and criticisms
See also: Open Data in the UK
Ordnance Survey has been subject to criticism. Most centres on the
Ordnance Survey possesses a virtual government monopoly on
geographic data in the UK, but, although a government agency, it
has been required to act as a
Trading Fund (i.e. a commercial entity)
from 1999 to 2015. This meant that it is supposed to be entirely
self-funded from the commercial sale of its data and derived products
whilst at the same time the public supplier of geographical
information. In 1985, the Committee of Enquiry into the Handling of
Geographic Information was set up to "advise the Secretary of State
for the Environment within two years on the future handling of
geographic information in the UK, taking account of modern
developments in information technology and market needs". The
Committee's final report, published in 1987 under the name of its
chairman Roger Chorley, stressed the importance of accessible
geographic information to the UK and recommended a loosening of
policies on distribution and cost recovery.
Ordnance Survey were criticised for contracting the public
relations company Mandate Communications to understand the
dynamics of the free data movement and discover which politicians and
advisers continued to support their current policies.
In response to the feedback from the[which?] consultation, the
government announced that a package of
Ordnance Survey data sets
would be released for free use and re-use. On 1 April 2010 Ordnance
Survey released the brand OS OpenData under an attribution-only
license compatible with CC-by. Various groups and individuals had
campaigned for this release of data, but some were disappointed when
some of the profitable datasets, including the leisure 1:50,000 scale
and 1:25,000 scale mapping, as well as the low scale Mastermap were
not included. These were withheld with the counter-argument that if
licensees do not pay for OS data collection then the government would
have to be willing to foot a £30 million per annum bill to obtain the
future economic benefit of sharing the mapping.
Ordnance Survey described an "enhanced" linked-data
service with a
SPARQL 1.1-compliant endpoint and bulk-download
Ordnance Survey historical works are generally available, as the
agency is covered by Crown Copyright: works more than fifty years old,
including historic surveys of Britain and Ireland and much of the New
Popular Edition, are in the public domain. However, finding suitable
originals remains an issue as
Ordnance Survey does not provide
historical mapping on 'free' terms, instead marketing commercially
'enhanced' reproductions in partnership with companies including
GroundSure and Landmark.
The National Library of
Scotland has been developing its archive to
Ordnance Survey maps for all of Great Britain more easily
available through their website.
This can be contrasted with, for example, the approach in the Republic
of Ireland in more recent times, where
Ordnance Survey Ireland
Ordnance Survey Ireland claims
regular copyright over its mapping (and over digital copies of the
public domain historical mapping). All
Ordnance Survey Ireland
Ordnance Survey Ireland maps
(historic and current) are available free to view on their online
Alastair Macdonald, Director of Surveys and Production at Ordnance
Directors of the Ordnance Survey
Great Trigonometric Survey
Irish national grid reference system
Ordnance Survey National Grid
United Kingdom Hydrographic Office
Map of the World
Maps of the UK and Ireland
Map Company, principal partner of the OS
Martin Hotine, founder of the Directorate of Overseas Surveys
(List of) national mapping agencies
Ordnance datum (sea level)
Ordnance Survey International
Ordnance Survey Ireland
Ordnance Survey of Northern Ireland
Romer, a device for accurate reading of grid references from a map
Ordnance Survey deals only with maps of Great Britain, and, to
an extent, the Isle of Man, but not Northern Ireland, which has its
own, separate government agency, the
Ordnance Survey of Northern
^ Ordnance Survey, Government of the United Kingdom, retrieved 21
^ Hewitt 2010, p. xix.
^ Porter, Whitworth (1889). "History of the Corps of Royal Engineers".
I. London: Longmans, Green, and Co: 167–68. Retrieved 14 August
^ Hindle 1998, pp. 114-115.
^ OSGR NS 826497
^ Hindle 1998, p. 117.
^ Seymour, W.A., ed. (1980). A History of the Ordnance Survey.
Folkestone: Wm Dawson & Sons. p. 71
^ A Description of
Ordnance Survey Large Scale Plans. Chessington: The
Director General at the
Ordnance Survey Office. 1947. p. 2.
^ Hindle 1998, p. 114.
^ a b Owen, Tim; Pilbeam, Elaine (1992).
Ordnance Survey – Map
Makers to Britain Since 1791. Southampton: Ordnance Survey.
ISBN 0-31-900249-7. [page needed] Freely available
online at the Ordnance Survew, Owen and Pilbeam
Ordnance Survey Maps Six-inch, 1st edition, Scotland, 1843-1882 -
National Library of Scotland. maps.nls.uk. Retrieved on 12 April 2014.
Facsimile reprint, Thomas Donald Historic
Map of Cumberland 1774,
^ Our history About. Ordnance Survey. Retrieved on 12 April 2014.
^ Seymour 1980, p. 139
^ "Key dates". London Fire Brigade. Archived from the original on 18
^ Harley, JB (1975).
Ordnance Survey Maps: a descriptive manual.
Southampton: Ordnance Survey. [page needed]
^ Oliver 2005, pp. 35, 54.
^ a b Oliver 2005[page needed]
^ Oliver, Richard; Hellyer, Roger (2002).
Ordnance Survey of Great
Britain: Indexes to the 1:2500 and six-inch scales. Newtown,
Montgomeryshire: David Archer. [page needed]
^ a b Main & Oliver 2015, p. 201.
^ Main & Oliver 2015, p. 14.
^ a b Main & Oliver 2015, p. 217.
^ Main & Oliver 2015, p. 221.
^ Hindle 1998, pp. 131-132.
^ Main & Oliver 2015, p. 220,221.
^ Main & Oliver 2015, p. 220.
^ a b Main & Oliver 2015, p. 42.
^ a b c Main & Oliver 2015, p. 222.
^ "Mapping the
Southampton Blitz 70 years on". Ordnance Survey. 30
November 2010. Retrieved 19 June 2012.
Ordnance Survey map of bomb sites". BBC. 30
November 2010. Retrieved 19 June 2012.
^ "Our history". www.ordnancesurvey.co.uk. Retrieved 1 February
^ "Our history". www.ordnancesurvey.co.uk. Retrieved 31 January
^ Morris, Helen (6 September 2010). "BT&D awarded map contract as
Ordnance Survey bows out of print". PrintWeek. Retrieved 9 September
^ "Frome company secures OS map contract". BBC News. 6 September 2010.
Retrieved 31 January 2017.
Ordnance Survey breaks ground at Adanac Park". Ordnance Survey. 3
April 2009. Retrieved 17 December 2009.
^ "Duke opens new
Ordnance Survey head office". Ordnance Survey. 5
October 2011. Retrieved 21 June 2012.
Ordnance Survey set to become a Government owned company". Ordnance
Survey. 22 January 2015. Retrieved 22 January 2015.
Ordnance Survey Change in Operating Model". UK Parliament. 22
January 2015. Retrieved 22 January 2015.
^ "Business Minister Matthe Hancock announces the appointment of Nigel
Clifford as the new Chief Executive of Ordnance Survey".
ordnancesurvey.co.uk. Retrieved 6 March 2015.
^ "A Very British Map: The
Ordnance Survey Story". Timeshift. 9
September 2015. BBC Four.
Ordnance Survey maps undergo their greatest innovation for over 200
years". Ordnance Survey. Retrieved 20 May 2015.
^ "Maps". Ordnance Survey.
^ "Custom Made". Ordnance Survey. Ordnance Survey. Retrieved 2
^ Schools urged to order free maps now! About. Ordnance Survey.
Retrieved on 12 April 2014.
^  Archived 1 October 2010 at the Wayback Machine.
Surveying guidelines". Business & government. Ordnance Survey.
Retrieved 14 November 2013.
^ "Carto Design team". Business & government. Ordnance Survey.
Retrieved 22 January 2014.
^ Public sector mapping agreements Business and government. Ordnance
Survey. Retrieved on 12 April 2014.
^ OS Master
Map products Business and government. Ordnance Survey.
Retrieved on 12 April 2014.
^ Arthur, Charles; Cross, Michael (9 March 2006). "Give us back our
crown jewels". The Guardian.
^ Chorley, RRE (1987). Handling Geographic Information. Report of the
Committee of Enquiry chaired by Lord Chorley. London: HMSO.
Greg Clark Written Questions, 1 May 2008 col. 668W Ordnance Survey:
^ Cross, Michael (21 August 2008). "
Ordnance Survey hires PR company
to lobby politicians". The Guardian.
^ "Policy options for geographic information from Ordnance Survey:
Consultation – Government Response". Department for Communities and
Local Government. Archived from the original on 19 September
Ordnance Survey launches OS OpenData in groundbreaking national
initiative". Ordnance Survey. 1 April 2010. Retrieved 16 April
^ "OpenData License Terms and Conditions" (PDF). Ordnance Survey.
Retrieved 5 April 2010.
Ordnance Survey has opened up its map data for free after a
long campaign. Find out what was released". The Guardian. 2 April
2010. Retrieved 16 April 2010.
Ordnance Survey Linked Data service proving popular with
developers" (Press release). Ordnance Survey. 17 July 2013. Retrieved
28 July 2013.
Ordnance Survey Maps". National Library of Scotland. Retrieved 21
Hewitt, Rachel (2010).
Map of a Nation – A biography of the Ordnance
Survey. London: Granta. ISBN 978-1-847-08254-1.
Hindle, Paul (1998). Maps for Historians. Chichester: Phillimore &
Co. pp. 114–115. ISBN 0-85033-934-0.
Margary, Harry (1992). Old Series
Ordnance Survey Maps of England and
Wales. Lympne. ISBN 0-903541-01-7.
Oliver, Richard (2005) .
Ordnance Survey Maps: a concise guide
for historians. London:
Charles Close Society.
Main, Roger J. P.; Oliver, Richard R. (2015). British Town Maps, A
History. British Library. ISBN 978-0-7123-5729-6.
"Homepage". Ordnance Survey. Retrieved 29 September 2005.
"History of Cartography". Academic research by the University of
Exeter. Archived from the original on 28 November 2005. Retrieved 29
Wikimedia Commons has media related to Ordnance Survey.
Ordnance Survey homepage.
OSMaps Web application.
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