??Karaköy Square has an important position in Istanbul, Turkiye, where commercial activities and history intersect over time. It had plenty of changes throughout history, especially during the creation of the square. The main focus of this research is: How Did Urban Modernization and Heritagization Transform Karaköy Square in Istanbul between 1910–1960? The research examines both physical and socio-cultural changes that contribute to Karaköy Square’s character. ??Through historical research, the thesis investigates the urban transformation that reshaped Karaköy Square’s physical landscape, by highlighting how historical buildings were demolished and how these changes affected the collective memory. It contains the creation of the square itself by demolishing existing structures and the result of the loss of urban heritage.