Italy is the country with the highest number of sites recognised as World Heritage by UNESCO and one of the nations with the highest density of sites of cultural interest both in Europe and in the world. Unfortunately, only a small part of these are completely and easily accessible, and certain of the most fragile sections of society, for example disabled persons, are in fact excluded from the possibility of visiting and discovering the said places. The research presented here represents an “experiment” in the application of the methodology of the Accessibility Plan to the monumental complex of the Opera di Santa Maria del Fiore in Florence, in other words the attempt to increase the degree of accessibility of the complex through a medium and long-term innovative strategic planning tool that takes into consideration not only material aspects (physical and sensory accessibility) but also aspects of an intangible nature, thus making it possible for people to fully understand the cultural meanings of the places, and focusing on the “experiential dimension of the visit” [1].