The report “Yggdrasil – The Living Nordic City” is part of the Nordic Cities Nature-Based Solutions Programme, supporting Vision 2030 to make the Nordic Region the world’s most sustainable. This initiative integrates nature-based solutions (NBS) into urban planning for sustainability, biodiversity, climate adaptation, and public health. The project evaluates the 3+30+300 principle: seeing three large trees from home, achieving 30% tree canopy cover, and ensuring public green spaces within 300 metres for all. Findings show Finland and Norway lead in compliance, while Iceland and Greenland face challenges. Recommendations focus on policy integration, native and diverse species for resilience, and equitable access to green spaces. The report highlights the principle’s flexibility and its importance in fostering sustainable, liveable Nordic cities.