The project addresses key challenges in realising widespread 5G deployments by extending cloud computing and virtualisation paradigms to the network edge and enabling multi-tenant access across urban infrastructures. By leveraging common smart city assets (e.g., small cells, street cabinets, edge computing nodes), 5GCity builds an open, multi-tenant platform that supports network slicing, orchestration of compute and radio resources, and the dynamic deployment of services. Its solutions are validated through city-wide demonstrations in Barcelona (Spain), Bristol (UK), and Lucca (Italy), showcasing edge-to-cloud connectivity, service programmability, and scalable neutral host operations.