Analysis of Trail Networks and Routes Optimization in Mountain Areas: New Tools in GIS Environment

This paper presents an automated GIS-based procedure for the analysis and optimization of hiking trails. A preliminary analysis of the topological and environmental features of a trail network is performed by evaluating a set of connection metrics describing both the local and global connectivity of its graph. Subsequently, the evaluation of optimal hiking trails has been implemented in an automatic procedure, which can use walking time, distance or upward slope as costs to be minimized. The evaluation of the hiking times for trail sections has been implemented in a GIS as a function of terrain slope. A Python script has been used to automate this process in GRASS GIS. The process was tested on the network of mountain trails in Trentino, an alpine region of Italy, where a digital map of the routes is accessible online. Empirical times and estimated trip times agree fairly well. The optimal paths vary based on the cost choice, i.e., whether the distance, trip time, or total height difference is minimized. It is therefore possible to integrate the determination of optimal hiking paths in a GIS, allowing the integration of this tool with all the other spatial analysis available in this environment.