A Berlin collective is campaigning for the German capital's entire city centre to be closed to cars and become a zone reserved for pedestrians, public transport, bicycles and scooters, for example.
A petition that counts more than 50,000 signatures is calling for the launch of a referendum, with a view to implement the project by 2027.
For the citizens behind this initiative, called Berlin Autofrei ("Car-free Berlin"), a car-free city centre ensures a better quality of life, cleaner air, more space for everyone, safer streets and, of course, is better for the environment.
The idea is to prohibit access to private cars in an 88sq km zone, delimited by the "S-Bahn-Ring" railway line that encircles the city centre.