Urban Digital Twins (UDTs) and Data Spaces have emerged as game-changing paradigms, facilitating the planning and development of sustainable cities. The presentation will take the audience on a journey into the future of cities, where UDTs are central to creating smarter, more resilient, and environmentally conscious urban solutions. It will showcase the synergy between UDTs and Data Spaces and their transformative potential to address pressing urban challenges and enable new business products and services. From reducing air pollution and fostering eco-friendly environments to mitigating climate change impacts and designing efficient, accessible, and sustainable mobility systems, the presentation will highlight how cities and communities can be reshaped for a better tomorrow.