The II. workshop of “Water in Istanbul: Rising to the Challenge” project, for which Istanbul Technical University Lecturer Dr. Çiğdem Özkan Aygün is a co-investigator and directs the field studies, was held on 17 March, 2022 at Marmara Pera Hotel.


“Hagia Sophia Subterranean: Subterranean Structures of Hagia Sophia and Their Relationship with the Historical Water Supply Lines” archaeological and engineering research, which started in 2015 within the framework of ITU Scientific Research Projects, is conducted with permission for surface survey from the Ministry of Culture. In this research study, a protocol was signed with the Society of Anatolian Speleology Group (ASPEG) and Hagia Sophia’s subterranean structures, water lines, wells, cisterns were unearthed, architectural surveys were made, 3D models were prepared and international publications were made. In addition, the studies were presented with many documentaries shot at home and abroad.


The research was later expanded to include the surroundings of Hagia Sophia, and subterranean survey of Topkapı Palace, Istanbul Archaeological Museum and the Hippodrome was made. All subterranean structures were documented by diving to areas filled with water and using ROV robot cameras. These studies were a starting point for the Water in Istanbul Project.


This project brought archaeologists, historians, engineers and social scientists together to investigate the water management infrastructure of Istanbul at two key phases in the city’s life: the transition from Byzantine to Ottoman rule and the period of population explosion beginning circa 1980. Since foundation, Istanbul has ‘thirsted for water’ – a problem that ruling authorities have wrestled with through time and those contemporary engineers, policymakers and urban planners are still attempting to address in the context of continuing population growth and rapid climate change. Focusing on the Topkapi area, which presented particular challenges due to its elevation, archaeological fieldwork and archival research, aimed to provide data for hydraulic engineers to model the Ottoman water management system.