Directness in Distance Directness in Distance
This criterium can be judged by using google maps and to compare the distance as the crow flies (shortest distance between start and end point of the cycle highway) to the real CH distance. A LEVEL-4 will be maximum 10% longer in real distance compared to distance as the crow flies.
As shown in the image the Cycle Highway F1 (Antwerp-Brussels) is closely following the train track and will have a high level of directness in distance, although some small crossing from one side to the other side of the train track are made.