Two years ago, an average neighborhood in the South Korean city of Suwon embarked on a radical experiment: For one month, the neighborhood suddenly got rid of every car.

Called the Ecomobility Festival, it was created as a way to help the city move much more quickly to a low-carbon future by helping citizens get a visceral sense of how that future could look.

“Usually in planning you do a computer simulation–an artificial picture of the future, and maybe a PowerPoint presentation,” says Konrad Otto-Zimmermann, creative director at The Urban Idea, who helped mastermind the festival. “We’re doing it in a different way: in a real city, with real people, in real time. It’s like a piece of theater where the neighborhood is a stage.”

When planning began, the neighborhood was filled with cars, and people typically drove everywhere, even pulling up on sidewalks to park in front of shops while they ran errands. “Most of the people could not envision how their neighborhood would be car-free,” Otto-Zimmerman says. “They simply said it couldn’t work.”

The planning process took nearly two years and countless meetings to get support from skeptics. Finally, in September of 2013, 1,500 cars were moved out of the neighborhood to parking lots elsewhere in the city. The city handed out 400 temporary bikes and electric scooters to neighbors, and set up a bike school to teach the many residents who didn’t know how to ride. Mail was delivered by electric vehicles. Shuttle buses ran every 15 minutes to take people to their cars.

The neighborhood transformed. Cafes and restaurants added new sidewalk seating, and the streets filled with people. It often looked a lot like car-free streets look during “Sunday Streets” events in other places, but the length of the experiment helped show how people could actually live without cars in everyday life.

“They live it for a month so their daily routines have to adapt,” says Otto-Zimmerman. “If you only have a car-free weekend, many cities do that, this is not exciting anymore. If it’s only a week, people can still reschedule their way to the dentist or whatever they have that week to work around it. It has to be a month in order to hit people’s daily agenda, so they really experience ecomobility in their daily life.”