**6. Conclusions**

This paper is aimed at providing a tool to help the one-day tourist in the difficult choice to plan an itinerary in a city. Indeed, a tourist often renounces relying on professionals of the sector who offer a service although complete, often pre-packaged and not taking into account her/his passions and preferences.

The proposed approach builds a network of points of interest (PoIs), proposing the city attractions but leaving the choice of the PoIs to be visited by the tourist. Based on the obtained graph, a multi-algorithms approach is provided to determine the optimal itinerary. The tourist is part of the multi-algorithms approach interacting with it and taking decisions.

An Integer Linear Programming (ILP) problem is introduced to find the optimal outward and return paths of the touristic itinerary and the multi-algorithms strategy is used to maximize the number of PoIs to be visited in the paths. Moreover, a case study demonstrates the approach efficiency and the steps of the procedure.

Finally, an app prototype has been developed and several use cases are being tested to iron out bugs before writing the final code. Future works will focus on useful developments of the application: integrating the possibility of making reservations at hotels, purchasing entrance tickets for the various sites and promoting sustainable mobility by providing simple but complete and updated information on how to ge<sup>t</sup> around the city (bus/metro time schedule, opening/closing hours of attractions, etc.); locating bike-sharing stations and bicycle parking; considering the cost as additional objective function to be minimized. Furthermore, Algorithm 1.2 will be object of further studies in order to improve its performance.

**Author Contributions:** Conceptualization, A.M.M.; methodology, M.R.; software, A.R.; validation, A.M.M., M.R. and A.R.; formal analysis, A.R.; investigation, M.R.; resources, A.M.M.; data curation, A.R.; writing–original draft preparation, A.M.M. and M.R.; writing–review and editing, M.R. and A.R.; visualization, A.R.; supervision, M.R.; project administration, A.M.M.; funding acquisition, A.M.M. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

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

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
