A shoe scanning system suitable for scanning an individual before access to a restricted access area, the system comprising: a detection unit comprising: a main detector for sensing a metal and/or unauthorized object above a surface onto which the individual can walk; a communication unit for transmitting a message to an indication unit (5, 51, 52) for providing instructions to the individual and/or to an assistant; and a processing unit connected to the main detector by a data link for receiving data and controlling the communication unit for sending a detection signal when the main detector indicates a presence of a metal and/or unauthorized object, wherein the main detector comprises sensing elements (122, 123) located below said surface; the sensing elements (122, 123) comprising: a short-range sensing element arranged to detect a metal and/or unauthorized object located above said surface up to a first maximal distance, and a long-range sensing element arranged to detect a metal and/or unauthorized object located above said surface up to a second maximal distance, the second maximal distance being higher than the first maximal distance characterized in that the processing unit and/or the main detector are configured to combine a result provided by the short-range sensing element and a result provided by the long-range sensing element so as to discriminate a metal and/or unauthorized object above said surface up to a detection threshold distance and in that the detection threshold distance is selectable in a range from a predetermined detection minimal distance to a predetermined maximal detection distance. a detection unit comprising: a main detector for sensing a metal and/or unauthorized object above a surface onto which the individual can walk; a communication unit for transmitting a message to an indication unit (5, 51, 52) for providing instructions to the individual and/or to an assistant; and a processing unit connected to the main detector by a data link for receiving data and controlling the communication unit for sending a detection signal when the main detector indicates a presence of a metal and/or unauthorized object, a main detector for sensing a metal and/or unauthorized object above a surface onto which the individual can walk; a communication unit for transmitting a message to an indication unit (5, 51, 52) for providing instructions to the individual and/or to an assistant; and a processing unit connected to the main detector by a data link for receiving data and controlling the communication unit for sending a detection signal when the main detector indicates a presence of a metal and/or unauthorized object, wherein the main detector comprises sensing elements (122, 123) located below said surface; the sensing elements (122, 123) comprising: a short-range sensing element arranged to detect a metal and/or unauthorized object located above said surface up to a first maximal distance, and a long-range sensing element arranged to detect a metal and/or unauthorized object located above said surface up to a second maximal distance, the second maximal distance being higher than the first maximal distance characterized in that the processing unit and/or the main detector are configured to combine a result provided by the short-range sensing element and a result provided by the long-range sensing element so as to discriminate a metal and/or unauthorized object above said surface up to a detection threshold distance and in that the detection threshold distance is selectable in a range from a predetermined detection minimal distance to a predetermined maximal detection distance. a short-range sensing element arranged to detect a metal and/or unauthorized object located above said surface up to a first maximal distance, and a long-range sensing element arranged to detect a metal and/or unauthorized object located above said surface up to a second maximal distance, the second maximal distance being higher than the first maximal distance