Prior to the advent of the compass, the primary means of geographic orientation while navigating in the Mediterranean was through the observation of the coastal landscape. On the high seas, spotting prominent and easy recognisable peaks served as a crucial element in determining the direction of travel. In coastal sailing, well-known natural or architectural landmarks, such as capes and islets, lighthouses and prominently located sanctuaries functioned as reference points for navigation. Once a vessel had reached the vicinity of a harbour, emblematic buildings emerging from the urban background provided the seafarers with a clear indication as to their location and guided them towards their landing place. The proposed paper presents a new methodological approach to the analysis of the dynamic perception of landscapes related to the activity of sailing, illustrated by the case study of the southern Adriatic coasts in the Roman imperial period and based on the adoption of the visibility analysis tools offered by GIS software. These are used to calculate cumulative viewsheds based on viewpoints scattered along sea routes known from ancient sources, in order to identify the coastal landmarks with the most relevant visual impact on seafarers and to quantify their dynamic visibility throughout the voyage.