Winding urban streets/grids

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Originally Posted by emathias

Grids aren't necessarily more efficient, it really depends on the use. They probably do make Manhattan more efficient, and maybe Chicago, but it's argue that is only because Manhattan is long and thin, so there just aren't many 45 degree trips. Similarly, in Chicago, the density of the city is pushed up narrowly along the Lake, which is also where diagonals are also more common. I don't think it's a coincidence that some of the most popular neighborhoods away from the Lake are bisected by diagonal streets.

In an unbroken grid, and trip that requires you to go an equal distance North or South and East or West is, by the rules of geometry, 40% longer than perfectly point-to-point trip would be, whereas the worst trips in Paris rarely add more than 25%. In cars, this can be worse if measuring in time rather than distance, but the addition of grand avenues and boulevards linking the most important points reduces that while leaving shorter routes for the pedestrians and Metro. And once you realize that to optimize for car traffic density goes down, it becomes apparent that grids really increase the perception of efficiency more than they actually increase absolute efficiency.

Grids are a bit like 1950s concepts of towers-in-a-park residential communities. Beloved of urban planners at a desk but, when it comes down to it, not preferred by real human beings. They’re not usually evocative of anything, and not so conducive to “placemaking”. Manhattan’s endless canyons might be one of the few exceptions to the former, but without that kind of density, or at the very least a good unbroken mid-rise streetwall, grids are downright boring.