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1. The main principles of the application of photogrammetric 
methods to the different stages of Highway Design 
The development of the technique of highway design during re- 
cent decades has implied that the requirements on the informa- 
tion regarding the topography and geology of the terrain have 
increased. One of the reasons is the introduction of more ad- 
vanced elements of road alignment. Another is the fact that the 
reguirements on the fitting of the road into the surrounding 
terrain or landscape from the points of view of environments, 
of aesthetics and traffic safety have increased. 
Due to this development the photogrammetric technique has be- 
come more important as a source of topographic information. At 
the same time, the importance of the photo interpretation tech- 
nique as a means of obtaining geological-geotechnical informa- 
tion has increased. 
The development of the application of photogrammetry to high- 
way design started during the early nineteen fifties. Among the 
more important contributions to this development may be mentio- 
ned the work carried out at the Bureau of Public Roads in U.S.A. 
by William T Pryor. Reference is made to (21). 
The discussions on the use of photogrammetry for highway design 
at the ISP-congress in London in 1960 meant a great step for- 
ward in increasing the interest of introducing modern aids in 
the old routine of highway design. 
The good timing, of the development of surveying technique, 
photogrammetry, electronic computation and automatic plotting 
since 1960 has also had a great importance for the success. 
This development has meant that the instruments have not been 
any limiting factor at the introduction, but they have been 
available mostly in due time. 
The problem has instead consisted of difficulties concerning the 
development of such a simple and logical technique, that the de- 
signer can regard the combination of photogrammetry, modern sur- 
veying, electronic computation and automatic plotting as a real