Some cities in Europe are undergoing a fascinating transformation: they’re getting rid of all of their road signs.

That’s thanks to a design concept called “shared space,” where urban planners drastically lessen the presence of traffic lights, signs, and barriers, encouraging all forms of transportation to share the road. There’s evidence that drivers often totally ignore road signs, so the heightened risk forces commuters to remain on high alert as they pass through an intersection, in theory leading to safer travel.

It’s part of a broader urban planning trend in the pursuit of walkable streets. In Barcelona, planners are sectioning off 9-block “superblocks” to insulate neighborhoods from heavy traffic. But shared space is walkable minimalism taken to the extreme — and it’s become a divisive topic in the places it’s been implemented.

Needless to say, it’s a pretty radical departure from the traditional rules of traffic design. But so far, there’s good evidence that it can work. After installing shared spaces, Ipswich’s accident rates with injuries fell from 23 over three years to just one per year. Pedestrian injuries at London’s Kensington High Street fell by nearly 60 percent. And in Drachten in the Netherlands, accidents at one intersection fell from 36 in four years to two in two years. But by stripping cities of their traditional traffic control systems, they leave disabled residents in the dark — and that’s sparked a powerful debate of how to balance ease of movement with all residents’ needs.

This is one of a series of videos we're launching in partnership with 99% Invisible, an awesome podcast about design. 99% Invisible is a member of Radiotopia.

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