With the Safe Digital City concept, Nordic Safe Cities aims to modernize the prevention system in the Nordic countries for the digital era. This initiative targets online harm and hate, assisting municipalities, civil society, youth, and police in safeguarding democracy and ensuring safety online. The Safe Digital City concept focuses on addressing the mainstreaming of conspiratorial and extremist narratives or recruitment into subcultures in local debates. These trends can mark the beginning of radicalization or fuel polarized and hateful discussions, posing challenges to democracy and crucial social media debates. The Safe Digital City consists of three main pillars: Mapping Hate: Using an algorithm, we track and map hate on social media, identifying hotspots, causes, and victims—essentially mapping the "local battlefield." Creating a Digital Mindset: We collaborate with cities to establish a structure for sharing information and fostering a digital approach among prevention professionals and civil society, enabling them to adapt their work to the online environment. Collaborative Online Prevention Efforts: We aim to move prevention efforts online, encouraging municipalities, police, and civil society to work together, find digital pathways for existing prevention work, and develop new strategies to tackle local problems.