The subject of this final paper is the Pazin Castle, also known as Castrum Pisinum or Mitterburg. Within the first section of the paper, the Castle is placed in a brief historical context and historically important facts related to the Castle are presented. Also, the first section is expanded with reasons for the emergence of a larger number of fortresses in the Istrian region, as well as their basic characteristics. Finally, in the last paragraph, the fortresses that were under the administration of the Pazin County are listed, along with their shared features. In the second section of the paper, the subject of the analysis is described in detail. The stylistic characteristics of Pazin Castle are indicated and its particularities are presented. This part also explains the establishment of the Ethnographic Museum of Istria - Museo etnografico dell'Istria and the Pazin City Museum during the 20th century, which are still located in the premises of the Castle. Through the third and fourth sections, the two mentioned museums and their permanent exhibitions are presented in more detail. Briefly mentioned are the modifications that have taken place at the Castle over the years, and the coexistence of the two museums within one building is clarified, along with the problems they encountered when setting up a new permanent exhibition. Also, changes made for the purposes of the new permanent exhibition are mentioned. Finally, considerations about the musealization of Pazin Castle are addressed. The conclusion is drawn at the end of the work, and the literature used for writing the final thesis is listed.