The project develops an innovative concept for digital analysis of complex urban environments, aiming to support decision-making in their planning and management. The digital system combines the city’s main physical subsystems (mobility, service distribution, waste collection, economic, social, cultural, environmental, etc.) with simulators based on artificial intelligence models. These simulators interact with each other in the digital world, composing a digital twin of the city itself, continuously learning from multiple sensory sources and updating themselves to represent the state of the physical city in real time. The project’s strategy is based on a modular approach: the digital city model can be initially developed for a limited part of the city (a neighborhood, for example) and for a small number of subsystems (mobility and air pollution, for example), greatly reducing the complexity of the problem and ensuring the development of a simple yet functional model.