Traffic flows like water

A couple of weeks ago we were in the Netherlands, staying in an apartment on the 39th floor of one of the tallest buildings in the country. It had windows on three sides of the buildings so we could see down to the everyday goings-on below, and it was fascinating to watch the traffic on the main artery in and out of The Hague, as well as the ebb and flow of the traffic on the city streets. Not only the traffic, but the people - it all looked like fluid mechanics. The flow of people off the trams and into the station, how the flow of traffic was blocked as a tram turned across the road, only to resume like an emptying test tube once the road was clear. Getting a real-time high-altitude view of a city "at work" really emphasises how every driver, cyclist and pedestrian is part of a much larger system that operates like blood flowing around your body. One slow driver and it causes a blockage and a buildup of traffic behind. A clumsy move at an intersection causes the same thing but the pedestrians flow around either side of the blockage like water passing a rock in a stream. The regular cycle of the traffic lights letting blocks of traffic through is like the plug being opened and closed in a sink that is constantly filling with water. If I'd been thinking about this site and blog, I'd have taken a time-lapse video to illustrate the effect, but I wasn't, so - sorry about that - you'll just have to imagine it ....