**5. Conclusions**

The urban realm is in constant and rapid transformation. Every day, new social, economic, and environmental needs arise, and cities have to evolve to satisfactorily overcome the challenges. However, this is not an easy task, as the number of variables and elements that conform the grea<sup>t</sup> system known as the city are uncountable.

Hence, dealing with complexity has become one of the biggest challenges for policymakers and urban planners. The fast rate of change in cities demands tailor-made solutions for each specific context, in very short periods of time, that respond to short-, medium- and

long-range time frames. Traditional planning has failed to do so, and this has to do, to a certain extent, with the approach taken. Humans like to think that a new invention can be the answer to all our problems, and the car was considered so. During the Twentieth Century, the car-dominated all urban planning processes, as it was seen as the ultimate alternative for mobilising goods and people within and around urban areas. Nevertheless, car-oriented planning was soon demonstrated to be unsustainable due to the extremely negative social and environmental effects that it has.

Taking more holistic, people-centric, and humble approaches to plan can be a more effective and equitable way to deal with complexity. Major urban planning and infrastructure interventions,on the other hand, in the urban realm take a long time to mature, and they can only be assessed after completion. Therefore, iterating planning processes can provide useful information about the rate of success of a given intervention to deal with a specific issue and allow the possibility to adjust the solution before being fully implemented. To do so, a huge amount of data has to be gathered and processed. On that account, technology plays a key role in urban planning, by providing high-quality open data, such as those collected from INEGI, and software, such as UrMoAC, with which urban planners can model at a high level of accuracy the state of a city. This allows a clear understanding of the issues of different parts of a city, permitting the elaboration of a hierarchy-based intervention.

Additionally, cities have to have a comparable and, ideally, standardised methodology to assess urban accessibility. By doing so, benchmarking, as well as the evaluation of public policies and urban interventions can be directly compared between cities of the same country, region, or even at a worldwide scale. This allows planners to argue to what extent a change is being made and at what rate. The current research project adds to that by using a transferable approach that can be replicated in different cities, making comparison of the results possible.

The results from the current research project demonstrate that taking an approach to urban planning based on accessibility provides many benefits in terms of sustainable planning. Accessibility measures permit obtaining highly disaggregated data of the performance of every part of the city regarding a specific variable, highlighting the areas with higher intervention needs and providing results that contrast how different transport modes perform for accessing a specific destination. Thus, using accessibility as the pillar of urban planning will allow cities into transform to more inclusive, environmentally friendly, and comfortable places to live.

Most cities in the world are still far from becoming 15 minutes cities, especially when whole metropolitan areas are considered, and the MMZ is not an exception. However, having this travel time frame as an objective should encourage policymakers, citizens and the private sector to transform cities from the local to the metropolitan level. It is also important to understand that in order to truly transform cities into better living environments, not only central areas need intervention, but the whole urban area. Everyone plays a key role in such a transformation, as it is necessary to agree that the current state of cities is going against sustainability and that an urgen<sup>t</sup> urban, social, economic, political and environmental transformation is needed.

**Author Contributions:** Conceptualisation, J.d.-J.L.-S. and R.A.R.-M.; methodology, A.L.G.-B., J.N.-B. and M.A.R.-M.; software, A.L.G.-B., J.N.-B., M.A.R.-M. and D.K.; validation, J.N.-B. and D.K.; formal analysis, A.L.G.-B., J.N.-B. and M.A.R.-M.; investigation, A.L.G.-B., J.N.-B. and M.A.R.-M.; resources, R.A.R.-M. and J.d.-J.L.-S.; data curation, A.L.G.-B., J.N.-B. and M.A.R.-M.; writing—original draft preparation, A.L.G.-B., J.N.-B. and M.A.R.-M.; writing—review and editing, D.K., B.L.P.-H. and J.d.- J.L.-S.; visualisation, A.L.G.-B., J.N.-B., M.A.R.-M. and J.d.-J.L.-S.; supervision, R.A.R.-M., B.L.P.-H., D.K. and J.d.-J.L.-S.; project administration, M.A.R.-M., R.A.R.-M. and J.d.-J.L.-S.; funding acquisition, R.A.R.-M. and J.d.-J.L.-S. All authors read and agreed to the published version of the manuscript.

**Funding:** This research received funding by the CampusCity Initiative of the Tecnologico de Monterrey. CampusCity Initiative is funded by Fundación FEMSA. Fundación FEMSA had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data used in this study were obtained from public databases and can be found in Table 1.

**Acknowledgments:** Special thanks to the Deutsches Zentrum für Luft-Raumfahrt (DLR) for making UrMoAC an open-source software and sharing relevant information about its use with our research team. The authors would also like to thank the Distrito Tec team, from the Instituto Tecnológico de Monterrey, for giving relevant information and feedback throughout the development of the entire project. We acknowledge as well the support of the California—Global Energy, Water & Infrastructure Innovation Initiative at Stanford University and the expedient proofreading by Josh Dimon

**Conflicts of Interest:** The authors declare no conflict of interest.The founders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; nor in the decision to publish the results.
