In his book ‘La mémoire collective,’ French philosopher and sociologist Maurice Halbwachs (1877–1945) defines collective memory as the way in which individuals and groups use mental images of the present to reconstruct a vision of the past. He believes that urban environments play an important role in shaping collective memory, suggesting that physical spaces such as buildings and streets serve as ‘memory anchors’ that reinforce attachment to place. A central concept of his proposition is that the city is the stage on which collective memories are manifested. In the context of Southeastern Europe, Halbwachs’s understanding of collective memory intersects with the intricate physical and cultural geographies of a region shaped by centuries of Ottoman and Hapsburg rule. After World War II, the government of the Federal People’s Republic of Yugoslavia sought to create a new collective conscience for a young, ethnically diverse, and unaligned socialist state with increasing global influence. Avant-garde postwar expressions in art, architectureArchitecture, and public space were used to shape a shared Yugoslav culture in major cities, small towns, and remote locations throughout the country. This chapter engages the theory of collective memory by examining public space in Mostar, the historical capital of Herzegovina. It focuses on two contested environments—the Stari Most (Old Bridge) with its adjoining streets and an Ottoman-era bazaar; and the Partisan Necropolis, a monumental spomenik with its ceremonial plazas and expansive gardens. These public spaces offer important insight into the often subtle, yet enduring divisions that continue to challenge Bosnian-Herzegovinian society.