A big underground water reservoir from the 6th century built in the Byzantine era in order to arrange the water supply for the city. It was built during reign of the Eastern Roman Emperor Justinian. The cisterns, a Roman-Byzantine invention, were used to store and distribute the water
That was obtained from the historical waterways; the first of which was the Hadrian’s Pipeline which carried the water from the north of the city in today’s Belgrad Forest. Later the Ottomans built monumental fountains in the city such as the Fountain of Sultan Ahmed the third in front of Topkapi Palace, or the Fountain of Mahmud the First in Tophane district.
336 cylinder columns, each of which 9 meters long are well preserved until this day and they make an impressive view where visitors enjoy . Two of these columns have Medusa heads under them as if these heads are supporting the columns. According to Greek Mythology Medusa is one of the female monsters of the underground world that has the power to gorgonize the ones that happen to look at her.
The reason this cistern is called ‘Cisterna Basilica’ is because there used be a basilica here at this sight.
The Basilica Cistern is open to visit every day. You can also visit the Cistern of Serefiye to enjoy a smaller version of a cistern that was recently renovated.
Tram Stop: Sultanahmet