Tourist motivation, as a core of travel behavior, significantly influences consumer intentions and has attracted academic attention for decades. A plethora of studies analyse sets of internal and external motivators, while methodologies that exclusively focus on a single factor, such as age, that can sometimes have a determining influence in multi-attraction destinations, are less prevalent. This study introduces a fuzzy logic approach to develop a new model for analysing the internal motivations of different-aged consumers in multi-attraction urban destinations. Fuzzy models, as a mathematical means of representing vagueness and imprecise information, have the capability of recognizing, representing, manipulating, interpreting, and utilizing data and information, which typically for urban tourist motivations, are vague and lack certainty. This research tests the model in a real-life setting, using the example of Novi Sad, a mid-sized European city, which is typical of many similar cities who are attempting to develop sustainable tourism by attracting older tourists. The new model shows how tourist motivations for multi-attraction destinations are affected by age, through a specially developed m-file for MATLAB, so that it can be applied and tested in other tourism contexts. Theoretical and practical implications for sustainable destination management and marketing are described.