Method for identifying the location of a fault on a faulty line of an electrical power supply network having a plurality of lines (10a-g), a plurality of inner nodes (K6-K8), which each connect at least three lines (10a-g) to one another, and at least three outer nodes (K1-K5), wherein the outer nodes (K1-K5) each bound a line and are provided with measurement devices which are used to measure high-frequency current and/or voltage signals; wherein, in the method, use is made of a device , to which the information needed to locate the fault is transmitted from at least one outer node (K1-K5) by means of a communication network , - after a fault has occurred on the faulty line, the measurement devices are used to detect respective times at which travelling waves arrive at the outer nodes (K1-K5) on the basis of the measured high-frequency current and/or voltage signals; and - the fault location is identified using the detected times; and wherein - one of the outer nodes (K1-K5) is selected as the starting node for the search for the fault location, wherein that node at which the corresponding travelling wave has arrived first is defined as the starting node for the search for the fault location; - starting from the starting node, paths to the other outer nodes (K1-K5) are determined, which comprise a plurality of lines (10a-e) and inner nodes (K6-K8), and those paths on which the fault location could be located, in principle, are selected; - a line on which the fault location could be located, in principle, is identified for each of the selected paths using the respective times at which the travelling waves arrive, and a potential fault location is determined for the respectively identified line; characterized in that - the power supply network is mapped to at least one tree structure in order to identify the paths; and in that - a minimum tree is identified by means of Kruskal's algorithm during mapping; and in that - the minimum tree and at least one further, non-minimum tree are identified in a power supply network having at least one mesh . - after a fault has occurred on the faulty line, the measurement devices are used to detect respective times at which travelling waves arrive at the outer nodes (K1-K5) on the basis of the measured high-frequency current and/or voltage signals; and - the fault location is identified using the detected times; and wherein - one of the outer nodes (K1-K5) is selected as the starting node for the search for the fault location, wherein that node at which the corresponding travelling wave has arrived first is defined as the starting node for the search for the fault location; - starting from the starting node, paths to the other outer nodes (K1-K5) are determined, which comprise a plurality of lines (10a-e) and inner nodes (K6-K8), and those paths on which the fault location could be located, in principle, are selected; - a line on which the fault location could be located, in principle, is identified for each of the selected paths using the respective times at which the travelling waves arrive, and a potential fault location is determined for the respectively identified line; characterized in that - the power supply network is mapped to at least one tree structure in order to identify the paths; and in that - a minimum tree is identified by means of Kruskal's algorithm during mapping; and in that - the minimum tree and at least one further, non-minimum tree are identified in a power supply network having at least one mesh . <EOS>