Metropolitan university campuses are unique places usually connected to cities and towns by motorised-transport infrastructures, originating an intense travel demand by car. This has triggered a growing concern about how policy action can be more effective to achieve sustainable mobility patterns. This paper aims to gain insight into how factors associated with what we term here as the “3Ss” approach (spatial location, socioeconomics and social behaviour) are influencing travel demand by car in the context of metropolitan university campuses. The daily mobility in the metropolitan Campus of the Autonomous University of Barcelona (UAB) in Greater Barcelona, Spain, provides the empirical focus. The obtained results explained the multifactorial origin of travel demand by car in the case study. First, it was seen how the age of the university mobile population and their weekly attendance at the UAB Campus were key factors in understanding the choice of taking a car in daily mobility. Second, statistical correlations were seen between car-weekly-km travelled by the university mobile population and factors such as gender, age, daily stay at the UAB Campus, and distance to the UAB Campus. The study also provides Autonomous University of Barcelona an excellent platform to reflect upon the elaboration of integrated transport policy packages. [ABSTRACT FROM AUTHOR]