## 4 Conclusions  
In this paper, we discussed the contribution of GIS in the field of planning of the electric networks with the aim to improve the capacities and the output of the national company of electricity and gas in Tunisia (STEG). A complete database related to the study area gathering all useful data was created. Different topographic maps and plans related to the study area were used, such as 1:25,000 topographic maps, 1:5000 plans, and Maxar 2020 background free image with a 1-m resolution. The use of similar free good-resolution satellite images can be a solution to the lack of data or non-updated data; however, the use of commercial Maxar images with a resolution ranging from 0.3 to 0.03 m will extend data accuracy. Moreover, GPS centimetric data were used to update electrical networks and to also verify the accuracy of the obtained data. Many thematic maps such as DEM and slope maps, land use map, and electrical networks maps were established. Based on GIS network and spatial analysis operations integrating slope and MV/LV network data, it was possible to conclude that the accessibility of each category of the network depends on slope value and direction. Different categories of roads were considered in the analysis of the vehicle transport network using the following criteria: speed, time, and hierarchy. The objective was the analysis of the shortest path, the calculation of routes according to a chosen impedance (best route with distance impedance; best route with time impedance), the generation of the origin-destination cost matrix to calculate average transport distances between service points or different localities (towns and villages) and the MV/LV transformer stations. We also performed the same type of analysis by using temporal impedance. The calculation of the service areas related to the accessibility of the paths according to different times was also established to organize service missions. The study and analysis of pedestrian technicians' movement network also enabled the development strategic routing plans. This study demonstrates, similarly to many studies related to the management of electrical networks based on GIS established in recent years around the world, the importance of GIS as a powerful tool for managing electrical networks. The planning of the electricity network will be important in urban planning and needs to be comprehensively evaluated in order to improve the quality of decision making and, consequently, improve the benefits of the investment. Panoramic display requires 3D visualization, which will be beneficial for realizing more realistic data visualization; for this reason, a 3D representation of the study area as well as the electrical networks has been created, providing a realistic visualization of the study area. The established Web GIS and 3D Web applications offer users the possibility to consult the made products via the internet. We were also able to integrate Google Earth and its 3D renders into the web pages and to add KML layers from the Google Earth community and from an API such as Google Maps. We have also been able to develop advanced 3D mapping applications. By using the elaborated website, we were able to create a link between Google Maps and the photos of the power poles with an explanatory video sequence to collect the maximum amount of information about the electrical network, and it was possible display different cartographic products at different scales. The present study did not consider factors such natural hazard factors, including weather and landslides. It does not consider human impact factors such as urban sprawl and urban density and agricultural and industrial impact. Taking these into account, all these factors in future works will significantly improve similar studies. This study opens wide perspectives; in fact, it would be possible to reproduce similar work established in that pilot zone in other zones related to the national Tunisian electricity and gas company STEG across the country.