This text is a reflection about the development of Islamic heritage in three different peninsulas where Islam has played an important role in the past: Qatar, Iberia, and the Balkans. The selection of these three spaces responds to the experience and academic specialization of the authors. There is a necessary simplification of the themes discussed due to the wide amount of information that has been used in the text, which includes a wide variety of approaches from different regions, languages, and traditions of scholarship. The aim of this exercise is to offer a comparative perspective that shows the complications and chances inherent to the definition of Islamic heritage beyond the limits of given communities and territories.