The development of orienteering maps
originally published in the Twenty five years of orienteering, 1986

Many people are nostalgic for the early days of orienteering on 1:25,000 or even 1:50,000 maps.
There was an excitement and challenge of the unknown, although events could turn into more of a treasure hunt than a race. The development of special O-maps changed the nature of orienteering. It still has excitement but the challenge is now one of a much fairer competitive sport, where mistakes generally originate with the individual rather than the map.
The O-map is an attempt to reduce the element of luck in orienteering. It is a map devised specifically for the navigator on foot. With a new map the information can be up-to-date, without the administrative detail and names of official maps. For the competitor, it indicates how easily an area can be crossed by showing the state of the ground (marsh, stones, vegetation), shows uncrossable barriers and includes a wealth of natural and man-made detail. The survey and cartography must make it easy to relate map to ground quickly, and above all the map must be legible. For the mapmakers the specification must allow him the possibility of showing all the detail adequately and it must be straightforward enough for the average orienteer to handle without previous cartographic experience.
Orienteers started to add detail to official maps or even redraw the maps in the mid-1950s. Early redrawn maps were usually three-colour (black, brown, blue) with open ground shown with a light brown tint and dense vegetation with a light grey tint. To a non-orientcer the idea of forest being shown as white rather than the traditional green on official maps was odd. The fact that the natural area for orienteering was forest made the green colour unnecessary and it was felt that to colour the non-forest areas would improve the legibility of detail in the forest. Before long the use of a fourth colour, yellow, for open areas was becoming common.

Defining Standards

The first IOF mapping book was published in 1969. This was in German and was the work of Jan-Martin Larsen (Norway), Christer Palm (Sweden) and Ernst Spiess (Switzerland). The book was later translated and published in English. The specification was for four-colour maps (black, brown, blue, yellow) and contained 60 symbols. The most obvious differences from current maps are the black dot screen for vegetation and the use of a brown line screen for wooded marsh. Among other symbols now long forgotten were the ‘L’ for felled areas, four dots for a ruin and the dash/dot line for a boundary.
The maps used for the World Championships are a useful guide to the development of orienteering cartography. These maps are always a showpiece for the state of O-mapping. The period 1968-1974 illustrates the changes. The 1968 Championship in Sweden used a redrawn four-colour map at 1:25,000. In 1970 in the DDR, the map was still four colour but at 1:20,000. The problems of showing large areas of thick vegetation with black dot screens with the effect on general legibility were clear. By 1972 in Czechoslovakia green appears on the maps. The scale was 1:20,000 and seven colours were used. Two different greens for vegetation and grey for rock outcrops were exceptional.
The 1974 maps in Denmark used a five-colour specification differing only in detail from today’s standard. It was not until the 1976 Relay map in Great Britain and then all maps in 1978 in Norway that the now standard 1:15,000 scale was used at a World Championship.
At this time the possibilities of showing several categories of dense vegetation and the various ways. of depicting them were under consideration. The alternatives of green or black screens were being tested. By 1971, green as a fifth colour on 0-maps was accepted as standard, as the legibility of detail below black or grey screens was poor. This was a time of much discussion and experimentation. New symbols appeared, such as the brown 'v', while others were given a more extensive classification, such as boundaries (stone wall, fence, uncrossablc fence, earth wall). At times there was an impression that one set of proposals were being overtaken by the next before they were put into effect. The publication of a definitive standard was needed.
At meetings during the 1973 Congress in Magglingen (Switzerland) the IOF Map Committee started work on this review under the chairmanship of lb Nielsen (Denmark). The basis for discussion was the then current Finnish map specification. Draft proposals were published and widely circulated during 1974. The result was the approval of a new set of map standards at the 1975 Congress in Boson (Sweden). The new ‘Drawing Specifications for International O-maps’ was produced in German and English — the familiar yellow book. The number of symbols had reached 100, reflecting the greater variety. of detail that could usefully be shown on O-maps.
I still remember those long meetings going through the symbols one by one, with lengthy arguments about, for example, whether the location of the feature should be at the foot of the ‘T’ or the point of the ‘v’ or at their ‘centre of gravity’. Such is the debate in map committee meetings. (The ‘centre of gravity’ of small point symbols is the location — for anyone still in doubt). The revised specification saw the demise of the ‘brown’ marsh. It was considered that blue for water features and brown for land form features was more logical and consistent.

Colour Blindness

There was much discussion on the particular green that should be specified. The PMS 339 is a ‘blue’ green which was an attempt to alleviate the problem of legibility for those orienteers affected by colour blindness. It was reported from Sweden that 11% of orienteers have this problem. A later specification has gone to a more ‘yellow’ green, but the ‘blue’ green has been kept as an alternative. To give a period of stability to the map standards it was felt that no further revision should be undertaken for at least five years.
By 1980 a further review was needed, At the Congress in Malente (BRD) a working group of the map committee was set up under the chairmanship of Jan Lien (Norway) to resolve the difficulties thrown up since 1975. The results were put to the 1982 Congress in Liege (Belgium) and approved. The specification is printed in English and German. It has the ‘Fantasia’ map on the cover and is the current standard.
Perhaps the most significant change introduced by the 1982 review was a general increase in line thicknesses. The previous minimum of 0.1mm was changed to 0.13mm. This was generally felt to be long overdue and the change allowed the adoption of the micronorm series of line dimensions. The 0.1, 0.2, 0.3... series of pens has now virtually disappeared, being replaced by 0.13, 0.18, 0.25, 0.35 ... The reason behind the new series is that any increase or reduction of a drawing from one 'A' size to another would produce line dimensions still consistent with the micronorm series. These sizes are not as odd as they appear at first sight.
Most of the symbol changes were uncontroversial — the possibility of differentiating between major and minor roads, maintained and ruined boundaries and so on. Some changes were simply to the design of the symbol itself — such as the increased thickness of the top line of a cliff. The brown ‘caterpillar’ for an earth wall was one of the casualties. The changes which caused most debate (which still continues in some countries) were to the symbols for thick vegetation (green) and for open land (yellow). No classification will suit all countries all the time. The aim of the new proposals is to set down categories which are specific according to certain principles, acknowledging that each category will cover a variety of situations.
The green colour indicates the degree of hindrance caused by vegetation. Green tints show that caused by forest (also restricting visibility), while green lines show that caused by low vegetation (visibility remaining good). Many different types of vegetation can be, have to be, included in the same category.
The yellow colour represents lack of tree cover. An area with no trees or bushes, offering good going, is shown with full colour. Scattered trees or bushes, still offering good going, are classified as semi-open — large yellow dots. The symbol reflects the scattered nature of the trees. Any ground which is predominantly without tree cover but where the going is slow is classified as rough open and shown with a yellow tint. Low vegetation in such an area will affect the going (felled areas) so green line screens were introduced to show the reduction in running speed. These lines have the advantage of representing low vegetation (where visibility is good) in forest as well as open areas. There will be several types of vegetation within any slow running category.
The acceptance of different situations coming under one classification is essential to the acceptance of the standard in different countries. Vegetation is one example. The classification of tracks and paths is another. A well-trodden footpath in one area may have to be shown with the same symbol as a poor or disused vehicle track in a different area. The advantage of having a worldwide specification is that it enables international contact and competition to take place freely. Such a specification is unique in the cartographic world and is a success of which orienteering can be justly proud.