Method for determining at least one scanning trajectory for scanning an area using a ground penetrating radar to detect underground assets (4a,4b,4c,4d,4e,4f) noninvasively by moving the GPR along at least one scanning trajectory, with determining at least one landmark object image feature by applying object detection techniques to images of the area to be scanned, characterized by • determining a position and/or type of at least one landmark object (1a,1b) corresponding to the at least one landmark object image feature in a scanning-area coordinate frame, the landmark object providing indication about a likely location of at least one underground asset (4a,4b,4c,4d,4e,4f), • determining a likely location and/or likely type of at the least one underground asset (4a,4b,4c,4d,4e,4f) connected to the landmark object in the area to be scanned by using the determined position and/or type of the at least one landmark object (1a,1b), and • determining the at least one scanning trajectory (3b,3c) using the likely location and/or likely type of the at least one underground asset (4a,4b,4c,4d,4e,4f), whereby the likely location and/or likely type of the at least one underground asset (4a,4b,4c,4d,4e,4f) are determined from at least the determined position and/or type of the at least one landmark object (1a,1b) by using a rule-based algorithm, wherein the rule-based algorithm encodes known craft-specific information, in particular building-industry specific information, on relationships between landmark objects and corresponding underground assets. with determining at least one landmark object image feature by applying object detection techniques to images of the area to be scanned, characterized by • determining a position and/or type of at least one landmark object (1a,1b) corresponding to the at least one landmark object image feature in a scanning-area coordinate frame, the landmark object providing indication about a likely location of at least one underground asset (4a,4b,4c,4d,4e,4f), • determining a likely location and/or likely type of at the least one underground asset (4a,4b,4c,4d,4e,4f) connected to the landmark object in the area to be scanned by using the determined position and/or type of the at least one landmark object (1a,1b), and • determining the at least one scanning trajectory (3b,3c) using the likely location and/or likely type of the at least one underground asset (4a,4b,4c,4d,4e,4f), • determining a position and/or type of at least one landmark object (1a,1b) corresponding to the at least one landmark object image feature in a scanning-area coordinate frame, the landmark object providing indication about a likely location of at least one underground asset (4a,4b,4c,4d,4e,4f), • determining a likely location and/or likely type of at the least one underground asset (4a,4b,4c,4d,4e,4f) connected to the landmark object in the area to be scanned by using the determined position and/or type of the at least one landmark object (1a,1b), and • determining the at least one scanning trajectory (3b,3c) using the likely location and/or likely type of the at least one underground asset (4a,4b,4c,4d,4e,4f), whereby the likely location and/or likely type of the at least one underground asset (4a,4b,4c,4d,4e,4f) are determined from at least the determined position and/or type of the at least one landmark object (1a,1b) by using a rule-based algorithm, wherein the rule-based algorithm encodes known craft-specific information, in particular building-industry specific information, on relationships between landmark objects and corresponding underground assets.