In America, we can’t even agree on the idea that cities are for people. We still decry bike lanes as a "war on cars," even in our allegedly progressive West Coast cities. So from where I’m sitting, the Barcelona plan is pretty fantastic: 186 miles of new bike lanes, a revamped bus system with better access and more frequency, more green space, and on and on.
But the coolest idea in it is "superblocks" (superilles in Catalan), a concept developed by Salvador Rueda, director of the Urban Ecology Agency of Barcelona. (Cities of the Future has a great interview with Rueda and a history of the superblocks concept — highly recommended. The Guardian also has nice piece.)
The idea is pretty simple. Take nine square blocks of city. (It doesn’t have to be nine, but that’s the ideal.) Rather than all traffic being permitted on all the streets between and among those blocks, cordon off a perimeter and keep through traffic, freight, and city buses on that.
In the interior, allow only local vehicles, traveling at very low speeds, under 10 mph. And make all the interior streets one-way loops (see the arrows on the green streets below), so none of them serve through streets.
