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SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962 
The castle in its environment 
This is a field of study which has scarcely been touched up to now, and one 
about which the aerial photograph can give a wealth of information. Using the 
aerial photograph the general environment can be studied, and an attempt 
made to assess its influence on the positioning of the castle. Thus we have, for 
example, castles situated within the bend of a river, such as the castle of 
Ter Aa (Utrecht) on the river Angstel, and the oldest castle of the Lords of 
Amstel, built on a “terp”, at Ouderkerk. 
Recording of excavations and restorations 
Finally, with the cooperation of photo-agencies, it has been possible to 
record the results of excavations and restorations on aerial photographs. This 
is a useful completion of the scientific data obtained from observation and 
survey. 
Several excavations that have been made after the Second World War have 
Fig. 2. Castle of Wulven: A. present manor house; B. site of the former eastle of Wulven 
C. unknown fortification