Fatigue is an insidious killer resulting in many fatal and serious injuries to vehicle occupants on road networks. Fatigue has on the whole had disappointing combined stakeholder national strategic emphasis in New Zealand, yet continues to emerge as one of the key factors in road crashes. Worldwide there is an increasing recognition that driver fatigue is over represented in road crashes. The understanding of fatigue (and a strategy to combat the issue) cannot be undertaken without a unified approach incorporating Education, Engineering and Enforcement, along with a detailed understanding of the location and cause of driver fatigue related crashes. The main objective of this research is to identify how terrain and geometric alignment impact on the occurrence of fatigue related crashes in New Zealand and their relationship to location and terrain. A review of the plots for the location of the crash clusters indicates a good correlation between the location of reported fatigue related crashes and the influence of terrain. The research indicates that approximately 80% of crash clusters are located in areas of low demand. Furthermore between 45% and 65% of all crashes have occurred in a location where the driver has traveled from a higher demand (load) area to a lower demand (unload) area.