Maps and Charts (Digital/ Raster or Printed)

Click on the links below to view the various map products we offer:
 •1:10 000 Orthophoto Maps
 •1:50 000 Topographical Maps
 •1:250 000 Topo-Cadastral maps
 •1:500 000 Topo-Admin Maps
 •1:500 000 Aeronautical Edition Maps 
 •1:1000 000 International Civil aviation Organisational World Aeronautical Charts
 •Aerial Photography

  •1:500 000 ICAO World Aeronautical Charts
 •1:1000 000 International Civil Aviation Organisation World Aeronautical Charts
 •Provincial Maps
 •1:2 000 000 Wall Maps

What is a map?

A map is a graphical representation drawn to scale of natural and artificial features (objects) on the Earth's surface. Some of these features such as roads, buildings or rivers, you would be able to see from a hill top or aeroplane. A map is a portrayal of the real world. Other features such as names of places, boundaries or heights are added to the map because of the importance that they have for the map user. A map can tell us about things that are happening around us, close by and far away. It gives us this information without having to necessarily be at that place.
 
Position (location):  A map gives the location or position of places or features. The positions are usually given by the co-ordinates of the place, either as the cartesian co-ordinates (x, y) in metres or as geographical co-ordinates (latitude and longitude) in degrees, minutes and seconds. The co-ordinates can be measured using the co-ordinate grid shown at set intervals along the borders of the map. The map user can, for example, find out that the position of Cape Town is 33°56' South latitude, 18°25' East longitude.
 
Spatial relationships:  A map gives us the spatial relationship between features. For example: What province is the neighbour of another province? Which side of the road is the river on? Is there a dam on the farm? Where is the nearest railway station?
 
Distance, Direction, Area:  We can determine a lot of information from a map such as distances, directions and areas. We can measure the distance from Johannesburg to Durban, determine that Pretoria is to the north of Johannesburg, or calculate the size of the Gauteng province. In determining distances and areas the scale of the map has to be taken into consideration. Directions are based on true north, but if you are using a magnetic compass then it must be remembered that the compass needle points to magnetic north, which is different from true north. The difference between magnetic north and true north is called magnetic declination.
 
Different types of maps:  Being a representation of the real world on a limited size of paper means that a map is restricted as to what can be shown. The cartographer has to select what to show and what to leave off. The cartographer is guided by what the main purpose of the map is, such as a road map, a topographical map or a thematic map. A road map emphasises the roads and towns but little else, while a topographic map, also called a general map, shows as much of the landscape, elevations, roads, towns etc. as possible. A thematic map is designed to depict a specific theme such as the population of various magisterial districts, the occurrence of crime in different districts, or annual rainfall.
 
What can I find on a map?

A topographical map shows natural and human made features on the Earth's surface and added to this are names and boundaries of importance. The features or objects are represented on the map as symbols in different colours as point symbols, lines and areas. The cartographer uses different colours and symbols for each type of object in a way that will make it easy for the map user to identify. Below are examples of what can be found on a 1:50 000 topographical map with the standard symbols: Road:

National freeway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
National route . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arterial route . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Secondary road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Railway (showing a station) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
River: Perennial (has water all year) . . . . . . . . . . . . . . . . . . . . . . . . . . .
Non perennial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pan: Perennial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Non perennial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Canal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Powerline (major lines only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spot height (elevation at a point) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Trigonometrical Beacon (with beacon number) . . . . . . . . . . . . . . . . . . . . . .
Built up area (High and Low density) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(Residential, commercial and industrial) Building (of significance or isolated) . . . . . . . . . .
Bridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cultivated Land . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Row of trees (where of significance) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wind pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Communication tower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Eroded area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sandy area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Boundary: International . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Provincial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cadastral farm (original farm) . . . . . . . . . . . . . . . . . . .
Protected Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Names of towns, rivers, mountains, major dams and other geographical areas

Positioning on the Earth’s surface

In order to determine where we are on the Earth's surface, we first need to know the size and shape of the Earth. To make things easier for us we assume that the Earth approximates a smooth mathematical surface. This surface is called a reference ellipsoid (a sphere which is flattened at the poles). Up until December 1998, the Modified Clarke 1880 reference ellipsoid was used in South Africa. Since January 1999 the WGS84 reference ellipsoid based on the Hartebeesthoek Radio Astronomy Observatory as the Datum point is used to define positions in South Africa. This co-ordinate system is known as “Hartebeesthoek 94”. The WGS84 ellipsoid is the reference figure used for Global Positioning System (GPS). To assist surveyors and others in their work, a network of approximately 60 000 permanently marked and accurately surveyed trigonometrical beacons and town survey marks has been established throughout the country, from which the position and height of any other point can be determined. This network is termed a passive control network since, besides marking an accurately surveyed point, the beacons do nothing to contribute to refining or monitoring its position. The all familiar trigonometrical beacons with their white pillars and black vanes which can be seen on mountain tops and on top of high buildings and structures represent this passive network. The increased use of satellite based positioning techniques, mainly GPS, has prompted this Organisation to install a network of active GPS base stations, known as TrigNet, which operate continuously in all weather conditions and at all times of the day. Instead of using the passive network, surveyors can use GPS receivers and data from the active TrigNet network to determine their position on the Earth's surface to within a few centimetres depending on the type of equipment used, the duration of observation, the suitability of the site etc. Positions derived from these networks are not only to make maps but also for the survey of civil engineering projects, such as the building of roads and water pipelines, land parcels for registration purposes as well as for numerous scientific applications.

Global Positioning System (GPS). To assist surveyors and others in their work, a network of approximately 60 000 permanently marked and accurately surveyed trigonometrical beacons and town survey marks has been established throughout the country, from which the position and height of any other point can be determined. This network is termed a passive control network since, besides marking an accurately surveyed point, the beacons do nothing to contribute to refining or monitoring its position. The all familiar trigonometrical beacons with their white pillars and black vanes which can be seen on mountain tops and on top of high buildings and structures represent this passive network. The increased use of satellite based positioning techniques, mainly GPS, has prompted this Organisation to install a network of active GPS base stations, known as TrigNet, which operate continuously in all weather conditions and at all times of the day. Instead of using the passive network, surveyors can use GPS receivers and data from the active TrigNet network to determine their position on the Earth's surface to within a few centimetres depending on the type of equipment used, the duration of observation, the suitability of the site etc. Positions derived from these networks are not only to make maps but also for the survey of civil engineering projects, such as the building of roads and water pipelines, land parcels for registration purposes as well as for numerous scientific applications.

Scale

The scale of a map describes the relationship between a distance or size on the ground. Amap has a scale because it is not possible to show the whole area at its true size. Ascale is normally given as a figure consisting of two parts, such as 1:50 000, the first part is a 1 and the second part 50 000. This means that 1 unit of measure on the map represents (equals) 50 000 units of measure on the ground -1cm on the map represents (equals) 50 000cm on the ground. Scale can also be given on the map as a scale bar, which helps the user to measure distances from the map. Different maps have different scales. A map with a scale of 1:50 000 is said to be a larger scale map than a map with a scale of 1:250 000. This is because an object on the ground is shown bigger on a 1:50 000 scale map than on a 1:250 000 scale map. A 1:1million scale map would be an even smaller scale map. However, the smaller the scale of the map the bigger the area that is covered on the map.

The effect of the different scales are shown here : 

From reality to Map

The cartographer has the task of bringing the real world to the map user. This is no easy task as the space available on the map is limited and the real world must be represented by symbols (points, lines and area fills). The process of making the map involves collecting data and making measurements (usually from aerial photographs) of objects in the real world: This information is then translated into understandable symbols and names and other relevant information is added which the map user can interpret to acquire knowledge about the real world. The Earth is round while the map is flat and so the cartographer has to project the round surface of the Earth onto the flat surface of the map. This process is known as a map projection. There are different properties of preserving true shape, area or distance. For a map to be useful it must be a good representation of the real world. This means that as things change, such as a new road or dam or houses, the map must be revised to show these changes. It is important therefore that maps show the date at which the information is valid. It is also these changes that make it necessary for maps to be updated at intervals. The updated map is shown as a new edition of the map with a new date.

Digital topographic information

Digital topographic information has been captured from the 1:500 000 and 1:50 000 map series. This information has been topologically structured and stored as features. The major features (such as all roads, railways, built-up areas, rivers and contours) of the entire 1:50 000 national series (1913 sheets) is available in a digital format. This information has been prepared primarily for use in geographic information systems (GIS) but can also be used in computer-aided drawing (CAD) systems (use in CAD leads to loss of attribute data). The applications to which the digital topographic information can be put are wide, similar to uses of a map, with the difference that users can utilise the power of the computer application software that they are using to do spatial analysis. This valuable national asset will continually be photogrammetrically improved, and updated to satisfy the nation's need for such information. This data is used by many organisations as well as individuals, both public and private, for planning, engineering, social and scientific purposes.

A Digital Elevation Model (DEM) is a collection of elevations (heights) in a digital form, giving the representation of the surface of the Earth. The DEM can be used to determine the height of a point or place, the terrain profile between two points, the visibility from a point.

The DEM is determined from photogrammetric (aerial photographs) measurements and computed in a regular grid of elevation points. Three levels of DEMs are available: the 400 DEM grid spacing with an absolute accuracy of ± 10m, supplemented with a grid spacing of 200m in the metropolitan and more mountainous areas. The second is a 50m DEM with a height accuracy of ± 2.5m, which has a grid spacing of 50m X 50m and is available in the metropolitan areas and growth areas. Both of these DEMs are available in the NES format and are referenced to the Modified Clarke 1880 ellipsoid. The above DEM information is supplied as a raster (matrix) of elevations with a limit on the east-west extent. Thirdly, the 25m DEM with a height accuracy of ± 2,5m, has a grid spacing of 25m X 25m and is referenced to WGS84 (Hartebeesthoek94), the format isASCII and is structured in a saw tooth formation or method yxz. The 25m DEM is available in most metropolitan areas and growth areas. As a result of the high demand for this data, the Chief Directorate has an ongoing programme to increase the 25 m DEM coverage. Digital maps as raster images are produced as digital copies of the printed maps at scales 1:50 000, 1:250 000 and other scales. The raster images are produced as a by-product from the computer-assisted cartographic system. These map images are most useful as 'backdrops' in various applications such as navigation systems, decision-support systems and value-added applications using the map as a reference. Digital orthophoto images are obtained by digitally rectifying aerial photographs. The digital orthophoto is a photographic image of the terrain, but more importantly it is true to scale and therefore accurate distances and areas can be measured. These images are popular as 'backdrops' similar to the digital map, but have the advantage over the digital map in that it is a real image of the terrain and not one interpreted by the cartographer. Both the digital map and digital orthophoto image are available on CD-ROM in TIF format.

How to obtain maps, aerial photographs and other services

To assist users in identifying the products required, index maps indicating the available maps and latest aerial photography are printed annually. These index maps are available free of charge and are obtainable from National Geo­-spatial Information in Mowbray or from the office of the Surveyors-General and other outlets.

How do I identify the map to order?

Each map covers a different area of the country and it is important to order the correct map. Each map can be identified by its unique number (e.g. 2830CB) and scale, or by name (E.g. 3318 Cape Town 1:250 000).

1. Each Degree Square is designated by a four figure number made up of the values of the Latitude and Longitude at its NW corner.
2. Each Degree Square is divided into sixteen 1: 50 000 sheets, each 15’ x 15’. These are lettered ABCD as indicated.
3. In the sketch the hatched area indicates the coverage of the sheet 2830CB of the 1: 50 000 series.

How to identify the aerial photograph to order?

Each aerial photograph covers a different area at a particular date. It is therefore possible to have more than one aerial photograph covering the same place, each taken at different times e.g. in 1958 and again in 1975 and again in 1993. Each aerial photograph is uniquely identified by its Job number, Strip number and Photo number. These three numbers are used in ordering the correct aerial photograph. The numbers can be obtained from the flight plan for the aerial photography job (Job number) or by visiting one of the offices where the aerial photographs are available for

Maps can be purchased either directly, by mail order or via our Internet site from the

National Geo-spatial Information

By mail : National Geo-spatial Information

Orthophoto maps can be purchased from most of the map outlets. Aerial photographs and enlargements of aerial photographs can be purchased only from the

National Geo­-spatial Information in Mowbray, but orders can be placed at the Surveyor-General in Pretoria, Pietermaritzburg and Bloemfontein.

Co-ordinates, heights and plans of trigonometrical beacons, town survey marks and bench marks may be obtained from the Chief Directorate: National Geo-spatial Information in Mowbray, or downloaded from the website.

Digital products are available by order from National Geo-spatial Information in Mowbray. Other services are available by arrangement directly with National Geo-spatial Information in Mowbray.

The prices for the maps, aerial photographs and other services are available on request, or on the Internet homepage.

Copyright : All the products of National Geo-­spatial Information are State copyright.

No products can be copied or reproduced by any means, including digital, without prior permission.

Workshops: Developing Map Use Skills

The MapAware workshop guides and encourages map users and geography educators to develop map reading skills and spatial awareness. The Land Information for Land Reform workshop capacitates personnel of the Department Rural Development and Land Reform to spatially identify and manage the delivery of land settlement of claims using maps, aerial photography, cadastral and title deed information.

Customised workshops are designed around specific user needs and may be given at a basic map reading level or an in-depth look at spatial information.

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