Passive markers are an essential tool for network asset management. They are buried alongside new networks as they are deployed or during maintenance work. Used for marking the network and its key points (connections, elbow, depth or direction change), they have demonstrated their unique ability to precisely locate and identify the network location regardless of the type of the soil in which they are buried (earth, sand, concrete, etc.). Passive markers can be identified in the presence of power supply networks, metal pipes, grids and other passive markers, provided that the installation conditions are met.