Digital Twin City is a new model of smart cities that aims at enhancing smartness, development, and management strategies. Which in turns, achieves better and more successful smart cities through adopting digital twin technology. The ‘New Administrative Capital’, NAC is considered the 1st smart city in Egypt, therefore, this research is concerned with assessing the role of digital twin technology as a tool to enhance smartness within NAC. The main aim is to adopt a holistic approach to achieve Smart Digital Twin City Model that can be replicated allover Egypt. To achieve the objective of the research, analysis of literature sources has been performed to identify the concept of digital twin technology and its influence on smart cities from an academic point of view; then, some existing digital twin cities have been analyzed to assess the impact of adopting digital twin technology in achieving smartness of cities from a practical point of view. Finally, a preliminary framework for utilizing Digital Twin (DT) Technology as a Tool to Achieve Smartness within NAC has been extracted.