For centuries, the underground world was conceptually relegated as a place of mystery, due to the lack of exploration and consequent knowledge. Ancestral attraction to an unusual and mysterious place, such as the underground, is still one of the main impulses for people to visit a cave. Geotourism is already well developed within show caves in many countries and, in some areas, can be considered to be one of the main tourist attractions. This chapter discusses show cave geotourism with particular emphasis on the Italian case, its stage of development, and the economic role caves have played in the tourism industry. The chapter also examines some economic data and considers some major Italian show caves in the context of an old, but still useful, theory about the evolution of a tourism attraction. A central question about geotourism is in regard to economic sustainability. In some situations, there is a positive answer to this question, particularly as the data shows that caves are effective tourism attractors and can have significant economic impacts similar to other sites such as important museums and well-known archaeological sites. At the same time, long-term exploitation of tourist caves highlights the limits of using such natural resources for tourism.