Cistern of Aetius

The Cistern of Aetius (Greek: ἡ Κινστέρνη τοῦ Ἄετίου), known since the Ottoman period as Çukurbostan ("sunken garden") and since 1928 as Karagümrük stadyumu ("Karagümrük stadium") or Vefa stadyumu ("Vefa stadium"), was a Byzantine open-sky water reservoir in the city of Constantinople, important for historical reasons. Once one of the largest Byzantine cisterns, it is now a football stadium in Istanbul.

The cistern is located in Istanbul, in the district of Fatih (the walled city), in the neighborhood of Karagümrük, about 300 metres (980 ft) southeast of the Gate of Edirne (the Byzantine Gate of Charisius, later known as Gate of Adrianople) of the city walls, along Fevzi Paşa Caddesi. It lies at the upper end of the valley which divides the fifth and the sixth hills of Constantinople.

Although according to a late tradition the erection of the cistern, which lay in the fourteenth region of Constantinople, dates back to the reign of Emperor Valens (r. 364–78), it is ascertained that it was built in 421 by Aetius, praefectus urbis in Constantinople in 419 and praefectus praetorio Orientis in 425, under Emperor Theodosius II (r. 408–50). The cistern was confused in scholarship for a long time with the cistern of Bonus or with that of Aspar: only in recent times has its identification become certain. The giant tank was oriented parallel to one branch of the Mese, the main road of the city which connected the Gate of Charisios with the center of the city passing near the Church of the Holy Apostles, and was supplied by the water main connected to the Valens Aqueduct. Due to its huge dimensions, in the Byzantine age the reservoir was often used as reference point to locate other buildings, like the monasteries of Prodomos of Petra, of the Romans (Greek: τὰ Ρωμαίου) and of Mara (Greek: τὰ Μάρα).

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