Sometimes road use can be inadequate to the real-time situation, particularly regarding the different times of the day, or the blending of all road users.

Both the city of Barcelona and Copenhagen have started to experiment intelligent LED lights in the road that signal rules in the real time, such as which form of transport has priority on the road, and when. In Barcelona, six boulevards alternate between restricting general traffic, freight, and residential parking. In Copenhagen, the cycling tracks can be widened during morning rush hour and then contracted when there are more pedestrians. It is thus the street that follows the natural rhythm of the city instead of the other way around.

Such experiences are expected to improve the transport flows and to revitalise certain areas.

Photo by City clock magazine on Flickr