The development of the Digital Twin City Platform is a research project in itself and RA0 seeks to answer the following research questions: (1) How should a digital twin city platform be designed to support and integrate a heterogeneous collection of data sets, methodologies and use-cases? (2) How can the digital twin city platform provide an automated process to generate all data sets required by the supported methodologies and use-cases from raw data? The Digital Twin City Platform is developed as an open-source project.and is based on open data. The platform provides all centre activities with input data and integrates all tools and models developed in the centre. It assimilate all output data generated in the centre and funtions as a vehicle for dissemination of results. In particular, the Digital Twin Platform shall use "Lantmäteriet" as the primary raw data source, use CityJSON as the primary data model, develop a pipeline for city model generation from raw data to CityJSON, create a server-based architecture for running simulations (via a REST API) and develop a user-interface and visualization framework in Unreal Engine.