Urban green spaces: 13.5% of Europeans live in areas complying with the 3-30-300 rule

Only 13.5% of the inhabitants of 862 European cities studied live in areas that simultaneously meet the three criteria of the so-called '3-30-300 rule', the benchmark for urban greening, according to a study by the European Commission's Joint Research Centre, with the University of Copenhagen, published in Nature Communications on 09/04/2026 and presented by the Joint Research Centre on 13/04/2026.

Conversely, the study (entitled 'Evaluation of European cities according to the 3-30-300 rule highlights the need to increase urban greening') shows that 21% of the urban population analysed lives in areas that do not meet any of the three thresholds. The central finding is that there is a structural deficit in urban greening, combined with a major territorial and social divide in access to nature in the city.

The study, carried out using satellite data, also highlights a highly contrasting geography. The best compliance rates are concentrated in Scandinavia, Germany and Poland, with Helsinki at 57%, Hamburg at 55% and Krakow at 47%. By contrast, Athens, Palermo and Cordoba lag far behind…