This thesis elaborates the characteristics, changes and sources of perception of the river Drava in medieval narrative sources. The analysis is based on 20 narrative sources created in the period from the sixth to the 16th century. Chronicles selected for the analysis are the ones created in the territory of the Hungarian-Croatian Kingdom, as well as in other neighbouring countries and for Croatian history relevant areas. The perception of the Drava River in this paper is examined using methods of eco-historic discipline and cultural history; terms describing the river are analyzed phylologically, and the perception of the river Drava is also considered in the wider framework of medieval perceptions of rivers, water and the environment. The majority of the work is focused on examining the perception of the river Drava as a borderline river, i.e. in narrative sources mostly depicted as the liminal role of the river. It is analysed how the formation of such perception was influenced by the perpetuation of ancient spatial views, and how did the nature of the dominant spacial obstacle influence the perception of the river. Examining the perception of the Drava River this paper seeks to find roots and diacronym continuity while the border perception and symbolism are compared with the real role, importance and characteristics of the Drava border of various historical political entities, particularly the Slavonian Kingdom. The role of the perception of the river Drava as a border is also placed within the scope of the perception of the subjectivity of the Drava-Sava interword, and the perception of the Drava watercourse is analysed in the paper.