This study aimed to identify the motivations that lead a particular sub-group of the millennial generation, namely, university students, to choose mountain areas as tourism destinations both in winter and summer. Through a focus group and a questionnaire survey targeting Italian millennial students (n = 2292), we first identified the main motivations that drive this choice. Second, we identified the level of importance for each motivation during both seasons. The findings revealed that millennials are guided by six main motivations in choosing mountain areas as travel destinations, each of which play different roles according to the considered season. The only exception is represented by the category of food and beverage, which is not influenced by seasonality. The results contribute to the literature on tourism and millennials, giving insight on the motivations that drive millennials' choices. Moreover, the results are relevant from a managerial point of view by providing important indications to managers and policy makers on the determinants of millennials' decisions.