Urban Digital Twins (UDTs) represent a recent application of Digital Twins (DTs), with the objective of replicating cities and providing a framework for urban planning. The utilization of UDTs provides a structured approach for the modeling and analysis of urban environments, incorporating a range of geospatial data presented in both two-dimensional (2D) and three-dimensional (3D) formats. This article details the process of processing, modeling, and integrating urban geospatial data into a Digital Twin. Two integrations for end-user platforms were demonstrated using a Geographic Information System (GIS) and an Unreal Engine (UE5) game platform. GIS-based dashboard systems provide professionals with the tools necessary to monitor, analyze, and create scenarios, thereby promoting collaboration between authorities and citizens. Game engines have the potential to play a pivotal role in the development of future UDTs by facilitating the creation of immersive experiences that aid users in comprehending their environment and promoting citizen engagement.

The 15-minute city concept has emerged as a framework for promoting more sustainable, inclusive, and accessible urban environments by enabling residents to reach essential daily services within a short distance from their homes. This study evaluates potential spatial accessibility to mapped points of interest in the Berceni neighbourhood, a socialist-era residential district in southern Bucharest, Romania. Walking isochrones were generated through network analysis and subsequently indexed and aggregated using the H3 hierarchical spatial system at resolution 10. Accessibility was assessed for seven social functions using three weighting specifications: 1:1:1, 3:2:1, and 5:3:1. The final analysis included 520 mapped POIs and 8465 H3 resolution 10 cells. The results reveal broadly consistent spatial patterns across the three weighting specifications, although the weighting assumptions influence local scores, the extent of high-accessibility areas, and the relative ranking of individual H3 cells. Caring has the largest mapped opportunity count and broad spatial coverage, whereas working and governing are the least represented functions and display comparatively low potential accessibility in several parts of the neighbourhood. A function-targeted scenario involving the addition of a childcare centre in the south-western part of Berceni produces a local improvement in working accessibility but does not eliminate the wider functional deficit. The findings demonstrate the applicability of combining network-derived isochrones with H3-based spatial aggregation for neighbourhood-scale accessibility assessment.

Urban planning has encountered numerous challenges due to the rapid growth of the cities in order to provide for suitable living circumstances, including satisfying the need for basic services, affordable housing for all residents, transportation and employment, and to fulfil the main Sustainable Development Goals (SDGs). The urban development must be guided by national and local authorities in order to maximize opportunities, requiring a harmonic coordination between policies and investments. The concept of Digital Twin has many opportunities to expand in the future, since it is constantly evolving, developing new features to provide the data required to optimize products and processes in a safe environment and decreasing the risks and costs of introducing new procedures. ArcGIS Urban is designed to improve urban planning and decision making and offers users the option of viewing multiple potential development perspectives and subjecting them to public review to ensure that the benefits of the community restrictions outweigh the costs.

In this article we started from the global warming trends due to climate change. These are leading to an increase in the heat risk index, particularly in areas where green infrastructure is lacking, where the population is dense and multi-storey residential buildings are dense. This is the reason why we first proposed a bibliometric study resulting from the growing interest in such analyses using GIS technology. The next step was the development of an automatic model based on specific features and its application to the Romanian capital, Bucharest, in order to identify areas in need of green infrastructure improvement, at the sector level and then at the neighborhood level. Three variables that determine the heat risk index were used: average summer surface temperature, percentage of area without tree cover and population density. The results highlight the sectors and neighborhoods of Bucharest where regeneration actions are needed. Concluding digital representations are made, related tree canopy and heat risk index for neighborhoods in Bucharest, as well as heat risk index map for prioritizing green infrastructure. This study is a good starting point for the substantiation of green infrastructure improvement policies, but also for studies to be developed at a more detailed level in the city analysis.