Developing young people's understanding of geography concepts requires teachers who have detailed, structured, interconnected, and accurate conceptual knowledge and understanding. Accordingly, this study focuses on pre-service geography teachers' understanding of the exemplar concept of contours on maps and discusses its implications for teacher training programmes. Data collected using a two-tier conceptual test and a questionnaire in a sample of 127 pre-service geography teachers indicated that pre-service teachers should not be perceived as a homogenous group with identical conceptual understandings and educational needs. The results highlighted the necessity to differentiate between pre-service teachers not only based on their conceptual understanding but also on the non-cognitive dimensions of concepts. Four types of pre-service teachers were identified based on success and certainty rates: successful-certain (SC), successful-uncertain (SU), failing-uncertain (FU) and failing-certain (FC). Both SU and FU types were characterised by low confidence in their related skills and a negative relationship to the concept of contours. The non-cognitive dimension manifested in opposite ways in SC and FC types. The specific educational approach required by each type is discussed, and implications for further research are presented.