This clear and enlightening 6 minute Youtube movie (in English) explains how and why the Dutch started to create their extensive network of cycleways.
It explains about the rising death toll, caused by the rising number of cars after World War II, and how public outrage changed the Dutch policies, from the 1970's onward.
Nesciobrug (bicycle/pedestrian bridge)
Bikepath along IJsselmeer
Scooter on cycle path: now a problem in urban environments.
Cyclepath in 't Twiske