Istanbul Historic Peninsula hosts diverse cultural heritage values that represent overlapping cultural layers lasting from the Ancient Greek city of Byzantion to the present city. This study examines the contribution of cultural landscape and historic urban landscape approaches to the conservation of heritage values in the Istanbul Historic Peninsula. Two of four UNESCO World Heritage sites, Hagia Sophia and Istanbul Land Walls are selected as case studies that are the architectural and urban scale components of the city’s image. This study aims to attribute to the world heritage sites of Hagia Sophia and Land Walls, which face the risk of loss of authenticity, integrity and outstanding universal value, the concept of cultural landscape, which enables the holistic and sustainable protection of the values and components of these sites. This study reveals the changing and continuing values of which are overlapped on a monument and a site.