The transformation of coastal or river waterfronts is among the most interesting phenomena in urban redevelopment because the coastal belt is rightly considered among the exceptional locations. When examining waterfronts, the coastal area in the northeast part of the old town of Koper is a very interesting laboratory because it was intensely transformed in a short timeframe. The urban and architectural development of the city of Koper and its urban areas experienced important turning points in the twentieth century, to which political and social events in the northern Adriatic significantly contributed. The key spatial changes in Koper included the construction of the newest northern Adriatic port, the Port of Koper, and projects such as construction of high-rise buildings by architect Edo Mihevc in the northern part of the old city core of Koper and in the Belvedere area. After 2000, new spatial solutions for further developing Slovenia's only port and three adjacent squares (Vergerio Square, Museum Square, and Nazor Square) on the northern side of the former island are being sought through public procurement or public urban and architectural competitions. Although the port is slowly implementing planned steps from the 2011 National Spatial Plan (e.g., dredging the first basin), residents feel that some of the selected squares still remain the most degraded areas of the city. The research describes some historical facts important for understanding the transformation of the location studied, the development of the construction of the Port of Koper, and some arrangements on the north side of the historic core. The analytical assessment of the first plans for a port at Koper and the contemporary comprehensive urban design for the spatial layout of the Port of Koper highlights key elements of spatial transformations of the port area (the waterfront, watercourses, traffic networks, urban structure, and specific territorial features) and individual arrangements in the northern part of the city's historic core. Those spatial elements of the port of Koper, for which there have been various proposals since the construction of the port began, are defined in the discussion. The conclusion offers concrete and general considerations relevant to understanding and evaluating current spatial proposals, and also relevant for designing future spatial proposals not only for Koper's coastal waterfront area but also for other waterfront and port areas. Interconnected areas - or the borders between the city and the port, or the port and the surrounding landscape - are becoming a key point in implementing modern town-planning concepts, thereby increasing the importance of their professional and innovative meaning. Ports fear that urban solutions will affect and restrict the main port activity. Similarly, cities fear that the expansion of the port traffic will generate more noise and negative environmental impacts in city areas. [ABSTRACT FROM AUTHOR]