The Basilica Cistern (Yerebatan Sarnıcı) is located in the Sultanahmet area of Istanbul’s Historic Peninsula. It was built in the 6th century by Byzantine Emperor Justinian I to supply water to Hagia Sophia and nearby palaces.

The cistern is 140 meters long, 70 meters wide, covering an area of about 9,800 m², and supported by 336 columns. Some columns were brought from ancient temples. The name "Yerebatan" means it is buried underground.

During the Ottoman period, it served the city’s water needs, and later it was forgotten. Since the 1980s, it has been restored and opened to visitors. The cistern is an important tourist attraction in Istanbul due to its historical architecture and atmospheric column arrangement.

Distance to Kaftan Hotel: 5 minutes on foot.