The NRD is a digital database of just about all roads in the
The geometry of the NRD is identical to the centre lines of the TOP10maps database of the Dutch Ordnance Survey. Therefore the geometrical accuracy is the same as maps with a scale of 1:10,000.
The NRD is a network consisting of junctions joined together by road segments.
A junction can be:
A logical consequence of this method is that a large number of road segments are essential to form such a network.
The NRD 2005, therefore, consists of 895,789 road segments and 643,071 junctions.
Figure 1. Example of road segments and junctions
The NRD is particularly important because it links various data sources to one another:
That makes it possible to analyse road safety in relation to the traffic volume and the features of the infrastructure.