Silivrikapi Hadim Ibrahim Pasha Mosque (1551) was built as a vizier structure by Mimar Sinan during his tenure as Chief Architect and has a single minaret and domes on a square layout plan. The mosque was characterized in several studies and concluded to be the pioneer of mosques with eight buttresses in terms of dome structure. The inner space features deep niches with pointed arches between protruding columns on the walls, which somewhat expand the space. The thick columns reach upwards to carry the dome placed on corner squinches. Buildings with similar layout plans and dome-bearing structures are observed in the development of Classical Ottoman Architecture, especially during the period of Mimar Sinan's influence as the Chief Architect. Dome-bearing system of the octagonal column layout in Silivrikapi Hadim Ibrahim Pasha Mosque is also seen in the Canbolat Pasha Mosque in Kilis, the Behram Pasha Mosque in Diyarbakir, Ali Pasha Mosque in Tokat, Dukakinzade (Al-Adiliyah) Mosque in Aleppo and Behram Pasha (Behramiyah) Mosque in Aleppo. The columns, adjacent to the wall, ascend to the cover and form the dome-bearing structure. However, characteristics of a second group of structures are mistaken for the former group at the lower window level. These structures have platforms on interior niches on the protruding columns in the walls and the columns do not go up any further. Therefore, the domes of these structures (the Bali Pasha Mosque in Fatih, the Haci Dogan Mosque in Kayseri, the Abdul-Qadir Gilani Mosque in Baghdad) are carried by pendentives or squinches instead of a system also supported by buttresses, seen in the aforementioned examples. Thus, there are two variations that appear to be similar on the layout plan but differ in dome-bearing structures. The fact that this layout type is observed at various places from the second half of the 16th century onwards in capital city Istanbul, Anatolia and the centers of other Ottoman provinces (Baghdad and Aleppo) indicates that the type was preferred in practice for a period of time.