Beneath the streets of Sultanahmet, the Basilica Cistern offers a different way to read Istanbul: not from a skyline or a mosque courtyard, but from the infrastructure that helped sustain an imperial city. Known in Turkish as Yerebatan Sarnıcı, or the “Sunken Cistern,” it was built during the sixth century under Emperor Justinian I. The Istanbul Provincial Directorate of Culture and Tourism describes it as the city’s largest cistern and gives its dimensions as 138 by 64.6 metres.
The structure is an underground water reservoir rather than a palace, despite the atmospheric nickname “Sunken Palace.” Its brick floor, waterproofed walls, vaulted ceiling and rows of columns belong to a practical system designed to store and distribute water. The provincial culture directorate says the cistern served as a water-distribution point around Sarayburnu and Bahçe Kapısı during the Ottoman period. That later use is one reminder that the building’s history did not end with Byzantium.
