## 5 Conclusions  
Our paper details a methodology for reconstructing historical cities when a map is the primary visual resource and archaeological remains are scarce. We applied this methodology to the 16 th-century map of San Cristobal de Laguna and divided the workflow into documentation, 2D and 3D processing and modelling, procedural generation, and visualization. Through our experience, we found that historical documentation is crucial, and a multidisciplinary team is necessary to overcome the challenges caused by the transformation of the city over time. Usually, it is unfeasible to digitize versions corresponding to the period of interest for buildings, urban elements, landscapes, clothing, etc. This lack of sources of direct information needs to be compensated for by information from historical professionals and knowledge from construction experts and engineers to obtain a precise approximation of the configuration of the city at that time. Given the large number of software programs required for a project of this complexity, experts in computer science are necessary for their use, adjustment, and interoperability. These programs have been used to transfer the city characteristics defined in the documentation to a visual 3D model using procedural generation. Finally, experts in computer graphics are needed to generate the final results by rendering the 3D model to obtain images, videos, and virtual reality results. Our methodology's utility and its application to San Cristobal de Laguna have been validated by the positive response that the project results have received in scientific and dissemination forums. Our 3D reconstruction provides visual results such as images, videos, or 3D web viewers that can be accessed on the project website to promote the city's heritage. It also raises the possibility of creating 3D content in forms of special relevance in the dissemination of cultural heritage, such as AR and VR products. Our methodology can guide the reconstruction of other cities from the same or later periods, provided there is a map available as a starting point. **Author Contributions:** Project management: F.P.N. and I.S.B. ; historical documentation: J.P.M., I.S.B. and F.P.N. ; historical consultation: J.P.M. ; 3D modelling: F.P.N., I.S.B., N.M.D. and J.H.R. ; 3D character modelling: C.M. and I.S.B. ; 3D model optimization: J.H.R. All authors have read and agreed to the published version of the manuscript. **Funding:** This study was funded by Fundacion Cajacanarias and Fundacion Bancaria \"La Caixa\" under \"Patrimonio Cultural en Canarias: del legado aborigen a la nueva sociedad canaria\". **Institutional Review Board Statement:** The study did not require ethical approval. **Informed Consent Statement:** Study did not involve humans. **Data Availability Statement:** All the elements in the results section including images, videos, 360 VR images, 360 VR videos, and a 3D web viewer for the 3D model are available from the project webpage torriani.iaas.ull.es. **Acknowledgments:** We acknowledge the support of [PERSON] from the city council of San Cristobal de La Laguna. **Conflicts of Interest:** The authors declare no conflict of interest. Appendix A Modified S skeleton subdivision of a closed Block B Modifications of the algorithm in [41] begin with (*)  
C(B) = {b\({}_{1}\), b\({}_{2}\),..., b\({}_{m}\)} ordered set of vertices describing the boundary of B (*) I(B) = {t, t,..., t\({}_{m}\)} logical information on whether the segment [t, t\({}_{m}\)!] has to be processed due to the presence of walls or voids  
SS = straight skeleton L = building zone subdivision L \(\leftarrow\)\(\emptyset\)  
SS \(\leftarrow\) computeSkeletonOffset(C(B), \(d_{\mathit{eff}}\)) //Compute the straight skeleton LS1, LS2, LS3 \(\leftarrow\)\(\emptyset\) //Temporal Land subdivision PS1, PS2, PS3 \(\leftarrow\)\(\emptyset\) //Temp.