REVISION DES CARTES 
COMPARATIVE STUDY OF THE PROCEDURES 
APPLIED IN THE FEDERAL REPUBLIC OF GERMANY 
TO THE REVISION OF THE TOPOGRAPHIC MAP | : 25000 
Prof, G. KRAUSS 
Bonn-Bad Godesberg 
1.- Introduction 
According to the Basic Law, surveying and mapping in the Federal Republic of Germany 
is not within the competence of the Federal Government but within that of the different federal 
states ("Lander"). Each federal state has a State Survey Office which, among others, is engaged 
in topographic land surveying and in the preparation and revision of topographic map series. Also 
in the former German Reich the topographic map series had not been prepared by one central ins- 
titution, but decentralized by the survey offices of the former German 'Lander''. 
2.- The Development of the Topographic Map 1:25 000 (TK 25) 
  
Since about 20 years a map series 1:25 000 exists for allareas of the Federal Republic 
of Germany [1] . All sheets have the same sheet line system. They are quadrangle maps covering 
6' in latitude and 10' in longitude, all referringtothe Prime meridian of Greenwich. Elevations 
are shown by contour lines. All elevations refer to the same datum. This uniformity in outward 
appearance has only been attained after the last war. The value of content, the quality of informa- 
tion and the kind of representation, however, differ on the sheets of the individual areas, as this 
map series had been prepared by the different federal states at very different dates. For some 
areas, the sheets date even back to surveys made in the first half of the last century. For the 
most part, however, the sheets had been created at the turn of the last century. 
In northern Germany most sheets have been mapped at 1:25 000 scale directly in the field ; 
in southern Germany they have been derived, for the most part, from large-scale topographic maps 
(1:5 000 and 1:2500 respectively). In northern Germany all sheets have originally been monochrome 
in southern Germany multicoloured already for a long time. In 1939, a uniform specification had 
been edited for the preparation of the Topographic Map 1:25 000 for the total area of the former 
Reich. In spite of this specification, there still exist differences on a large number of these map 
sheets. Such differences appear in particular in the extent and kind of representation, e.g. that 
of settlements. These differences are of considerable importance for the revision of map series. 
In our densely populated country this map 1:25 000 has to fulfil important tasks. Nearly 50 per cent 
of all sheets published in the normal (regular) sheet line system are prints of the Topographic Map 
1:25 000. Moreover, plastic foils 1:25 000 and enlargements 1:10 000 are required to a considerable 
extent as basic material for planning purposes. 
3. - The State of Revision 
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Just as in other states, also in Germany the necessary attention had not been paid to the 
revision of map, series in the past [2]. In Northrhine-Westphalia e. g. , in 1951 still about 1/3 of 
all sheets of the Topographic Map 1:25 000 had not been revised in detail after their creation at 
the turn of the last century, i.e. since more than 40 to 50 years. After 1945 the map 1:25 000 had 
been urgently required for reconstruction purposes. For this reason the State Survey Offices had 
been forced to pay special attention to the revision of this map series. This was the reason why in 
the two last decades considerable endeavours have been made, new procedures have been intro- 
duced, above all, the aerial photograph has been used to an ever increasing extent, and most sheets 
have been revised severaltimes. In spite of this, even today there are on sale some sheets which 
have not been revised in detail since nearly 40 years, i.e. where the total of represented features 
has not completely been checked and revised. 
The Topographic Map 1:25 000 is not continuously revised but, in general, at certain in- 
tervals, i.e. cyclically. The cycles differ according to the structure of the area concerned, they 
amount from 3 to 12 years. These long-range programmes are, in general, established according 
to units of the Topographic Map 1:50 000. In Northrhine-Westphalia e. g. nowadays the sheets of 
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