My route to work takes me over the Nesciobrug, a bridge named after a Dutch writer whose pseudonymn means "I don't know". It's located in the east and connects Amsterdam to a series of artificial islands. From the southern bank, someone wishing to cross the canal has a choice to make. A set of stairs is the clearest connection from the ground to the bridge, but it's steep and at odds with the bulk of a standard Amsterdam stadsfiets. Alternatively one can follow the gradual incline that goes counterintuitively away from the water until it wraps itself like a noose around the same trees that obscure its design. From an aerial view, the ramp is easily understood. At ground level the gateway appears either as a detour or simply the wrong direction, and in either case, a type of risk. The few people I spot every week lugging up their bike remind me of my own first choice, the most direct, which would not compromise the short window I gave myself to reach my job interview on time.
The old Amsterdam center has a different visibility. Streets wind around corners and limit the number of people that can be seen, or what unsightly problems might lie on the horizon. In the more open space leading to Ijburg, approaching the intersection of the A1 and A10 highways where the commuters and trucks and signifiers of overpopulated modern life are busily moving overhead, the "I don't know" bridge marks for me a sort of turning point. This impressive bridge could be a monument to the fietsgangers  of Amsterdam 1. The English word "bikers" can conjure up images of fat, leathered men on crotchrockets. The Dutch word "fietsganger" is simply ugly because of its sound. -- there are few pedestrians, and by law although not by practice, motorcycles are forbidden -- but its height is only to accommodate the large cargo ships carrying anything from coal to cars to trash down the Amsterdam-Rijnkanaal, and the manufactured, mostly residential living space that comprises Ijburg on the other side has all of the contours of worried planners trying to solve a problem, leaving behind issues of quaintness and the scenery it might demand. The architecture isn't strictly pragmatic, but the grid is palpable despite the variation and color, which came out of a (discussed, debated, and eventually approved of) decision to split the commissions for new housing among different firms, who in turn set out to distinguish themselves. Spaces for recreation are deligated and green, and vary in usefulness depending on the weather. On most days a street corner will have an occupied trampoline with a sign that says "take of your shoes" or "kids only", and further down the same block, suggesting for me the beginnings of a liveable neighborhood, there is often a group of middle aged guys from the bike shop, who I cannot imagine strolling to the nearest park to see the rabbits or the young couples who acted like them to fit into the atmosphere of Ijburg. On this point a woman recently said to me: it's too bad, they should have installed more balconies and terraces; which is to say, Ijburg had the right idea but there's room for improvement in the planning.
The original planning was far more ambitious, with far less room for trampolines. J.B. Bakema and J.H. van den Broek, 1964. NAI Collection. This sketch of the Pampus Plan from 1964 is what a bird would have seen if he escaped the Artis Royal Zoo and flew directly upwards. It proposed a city extension to hold 350,000 people. I find the drawing itself quite remarkable for all of its empty space, the calm, the disinterest in anything outside its parameter, besides perhaps the forest of dots at the bottom of its frame. The preservation of natuurgebieden became of great public concern in the 1980's, and helped to structure the national plan for population expansion that mobilized in the two decades that followed. To avoid a sprawl from one city to the next, rijksbufferzones were instituted as no-build areas. I've noticed they share some ground with the pre-WW1 Stellings van Amsterdam, the defense line that circled the city with a combination of forts and dykes that could be triggered to flood the area marked in blue below.
A nice map of the defense line is available from the Provincie Noord-Holland. I've asked if a public GIS file is available, which I'd like to overlay with the unavailable "open data" from the federal government of rijksbufferzones. A third layer worth investigating are the UNESCO World Heritage sites, which would help explain the survival of these green spaces.