This study aims to identify the reasons why people visit the Holocaust Museum of Porto (HMP) and if other variables (sociodemographic ones, visitors’ similarity with Jewish community members, their knowledge of dark tourism, and experience with other Holocaust-related destinations) also influence such motivators. A quantitative analytical, observational and case-control study was conducted based on a survey of 488 respondents who completed a self-administered questionnaire at the HMP. Statistical data analysis included descriptive statistics, an exploratory factor analysis, a confirmatory factor analysis, convergent validity (through composite reliability and average variance extracted), and discriminant validity (through square roots of the AVE values). The findings reveal that visitors are drawn by factors such as novelty and knowledge-seeking and that the motives for visiting the museum differ according to their sociodemographic characteristics, visitors’ similarity with members of the Jewish community, and their knowledge of dark tourism and experience with other Holocaust-related destinations. Sociodemographic variables, previous practices related to the Holocaust and similarity have an impact on the drivers behind visiting dark places. These results contribute to dark tourism literature with an improved understanding of tourist behavior toward Holocaust memorial museums. In addition to filling a gap, it provides a comprehensive insight into the specific motivators behind visiting the HMP, possibly allowing this museum to better design tourist experiences, thus increasing the potential to attract more visitors and keep alive the memory of such atrocities that cannot be repeated.