The case study presents the operation of Budapest100, an annual architectural and cultural festival that has been running successfully for more than ten years and has taken place every year with the involvement of hundreds of volunteers. The initiative is considered outstanding in the field of effective volunteer coordination, community building, and heritage preservation both in Hungary and on the international architectural and cultural scene. In this study, I first present the operation and structure of the project, focusing on the process of volunteerism and the role of volunteers. In addition, I analyze the motivational factors of Budapest100 volunteers as described by themselves in the Hungarian Volunteer Motivation Questionnaire. Based on the qualified free-word answers of 656 volunteers who joined the Budapest100 project in 2019, 2021, and 2022, the result of the analysis shows that a their motivation is defined by the following sequance of motivational factors: understanding, reciprocity, career development, self-esteem, social interactions, and values. This sequence of motivations clearly demonstrates which motivations stimulate the volunteers' participation in cultural programs.

Keywords: community building, volunteering, cultural festival, volunteer motivations,