There's been a marked tendency to replace intersections with roundabouts and shared spaces ( https://en.wikipedia.org/wiki/Shared_space ) in many places, including the outskirts of Lisbon (as well as a few legendary mazes in Britain). There was even a BBC report on the latter (which I can't find right now, as usual, only a follow-up: http://www.bbc.com/news/uk-33303031 ). Drawing a (admittedly inaccurate) parallel wi…
re shared spaces, from the wikipedia: > Hans Monderman and others have suggested that, by creating a greater sense of uncertainty and making it unclear who has priority, drivers will reduce their speed, in turn reducing the dominance of vehicles, reducing road casualty rates, and improving safety for other road users. clearly, Hans Monderman has never driven in Mumbai, India.
But for modest to high volume traffic, roundabouts are better (although if the traffic flow is constant, you usually have to place the crossings a bit further away from the center of the roundabout, which makes it a little harder on elderly pedestrians to go fully "across" since they have to walk the extra distance).