An alarming study on air quality in school environments came as a bombshell to parents with children at Maria Boodschap primary school in Brussels. The outraged parents, including architect Annekatrien Verdickt, decided to cordon off the street every Friday until the competent authorities took action. The citizen movement Filter Café Filtré was born. This was in 2018, the year Greta Thunberg organized her ‘Skolstrejk för klimatet’. These actions sowed the seeds for OpenStreets, a unique experiment where streets come under temporary self-management.

The audacity of blocking a street captures the collective imagination. Mediagenic images of school-gate actions get picked up eagerly by newspapers and TV news, causing the action to spread like wildfire to other primary schools. In the end, actions were held at no fewer than 173 schools in Brussels and elsewhere. The success of civil disobedience is mainly political; the issue sets the political agenda in no time. The Covid pandemic a few years later gave the citizen movement an extra boost.