Samenvatting
It is stated that the more complicated character of an urban road network leads to another estimation of the relation between average speed and intensity than usual on interurban highways. The average speed is deduced on an indirect way, going out from the relation: vehicle mileage (cars) per time unit is equal to the product of the average speed and the average number of vehicles per time unit at the same time. The latter is investigated by means of aerial photography.