The Active Cities project, a collaborative initiative involving eight European municipalities and several knowledge partners, provides a roadmap for transforming urban environments from car-centric spaces to human-scale areas that prioritize walking and cycling. Conducted between 2022 and 2025 and co-funded by the Interreg North Sea programme, the project demonstrates that strategic street interventions deliver multifaceted benefits, including improved public health, enhanced mobility equity, and increased climate resilience.