16 
more developed technique applied in the mapping process. The use 
of electronic measuring devices, block-triangulations, highly 
developed data systems, colour films and carefully checked came- 
ras, images and stereoplotters has made it possible to produce 
large scale maps of a quality sufficient for detailed planning 
of urban areas. 
Table 5. Production of Maps 
Type Area, sq. km 
1968 1969 1970 1971 
Official Maps 
Orthophotomaps, 1: 10,000 8,150 6,650 5,250 44515 
Photomaps, " 2»350 1,750 450 2,000 
Contour maps, M 10,500 11,250 10, 175 9,5175 
Orthophotomaps, 1:20,000 2,500 4, 100 12,350 9,850 € 4 
Photomaps, " 2,920 2,480 6, 175 4,000 | 
Contour maps, " 4,550 4,950 11,025 8,700 
Other Maps 
1:400 - 1:500 125 155 180 200 
1: 1,000 730 840 780 660 
132,000 1,200 1,000 1,200 1,000 
1:4,000 — 1:$5,000 4,500 4,500 3,200 1,900 
1: 10,000 5,000 3,000 4, 500 5,200 
1320,000 = 1:25,000 11,500 13,500 12,300 13,200 
1350,000 - 4,700 700 2,000 
Total 23,095 27,695 22,660 24,160 
The. increase in the application of numerical photogrammetry such 
as aero-triangulation, digital terrain models, cross-sectioning 
and digital mapping cannot be expressed in accurate figures 
because of the lack of available statistics. A rough estimation e o 
shows that the increase in obtaining digital data by photogram-