Abstract: A system for marking hidden utilities such as buried gas lines, valves and the like includes a marker having highly visible indicia indicating the type of utility on one face and which is bonded to a permanent object adjacent the location of the utility. The highly visible indicia is light reflective or fluorescent or both. The indicia are also recessed in the face of the marker for protection. The marker is affixed to a permanent object such as a curb face or surveying monument in the general location of the utility. The indicia on the marker represent the type of utility and the marker may also contain indicia representing the distance and direction from the marker to the utility location. The system can be provided in kit form which includes, in addition to the marker, a bonding material for affixing the marker to a permanent object and a marker for inscribing information relating to distance and direction on the marker.