Nowadays tourism is one of the fastest growing branches of economy. There is almost no part of the world that is not involved in tourist activities. In this respect, Dark tourism, as a composing part of the tourist offer, is only beginning its development. Dark tourism is bursting with new possibilities, challenges, new ideas and activities and its importance will continue to grow as out everyday life becomes increasingly hectic. The tourists grow more challenging, so there is a demand for non-standard and unusual tourist product. Selective forms of tourism focus on activities or environments that are attractive to a small number of tourists. Globally, there appears to be a new tourist, modern tourist who is no longer interested in 4S (sun, sea, sand, sex), but in 6E (escape, education, ecology, entertainment, excitement, experience). Modern tourists look for adventure, interaction, participation, getaway from everyday life and new lived experience. This is a great opportunity which encouraged me to write about dark tourism that is hardly present in Croatia. This thesis contributes to the development of dark tourism on local, regional, state level and presents a potential example for other supporters. It shows that it is possible to exploit the wealth of resources available in Croatia for the development of this selective form of tourism in a quality way. The dark side of Pula’s underground tunnel is a project which would certainly enable the arrival of new tourists, enrich tourist offer, encourage other stakeholders to include similar products in its offer and thus to initiate the development of this world-known form of tourism. For us it represents recognition of Croatia as a destination that provides a wide range of offers and a country which is able to compete with every other destination.