The present diploma thesis aims at studying the relative road accident risk by driver age, as a function of selected geometrical characteristics, such as those contained in the database of the Department of Transportation Planning and Engineering of the National Technical University of Athens (NTUA). The lack of vehicle-kilometer and passenger-kilometer data has led to the introduction of the concept of the “relative road accident risk”, which allows the analysis without using traffic data. The statistical analysis has led to the development of two mathematical models.. The first model correlates the downward gradient of the road with the age of the driver, the number of traffic lanes per direction and the direction markings on the road axis. The second model correlates the right-turn with the age of the driver, the number of traffic lanes per direction, the direction markings on the road axis and the central median. The application of the models showed that young drivers between 18 and 36 years old are more likely to get involved in road accidents when the characteristics of the road are unfavorable (e.g. no direction markings), while older drivers between 37 to 55 years old are involved in more road accidents than usually when road characteristics are favorable.