Category: Infrastructure
Type: Cistern
Location: Yerebatan Ave. Alemdar, Fatih
Date: 527-565
Designer: Unknown
Period: Eastern Roman (Byzantine) Empire
Photos: Yerebatan Sarnıcı Müzesi, 2026 (yerebatan.com)
Built by the Byzantine Emperor Justinian I between 527 and 565, the Basilica Cistern, popularly known as the Yerebatan Sarayı, stands as Istanbul’s largest underground water reservoir with a capacity of 80,000 tons. The colossal rectangular structure covers approximately 10,000 square meters and features 336 marble columns, each 9 meters high, arranged in 12 rows. These columns exhibit various architectural styles, including Corinthian and plain capitals, many of which were repurposed from older Roman buildings. A defining engineering feature is the 4.80-meter-thick brick walls coated with a special waterproof Khorasan mortar to prevent leakage. Historically, the cistern supplied water to the Great Palace and surrounding areas via the Hadrianus aqueduct system and continued to serve the Topkapı Palace after the Ottoman conquest. It was “rediscovered” for the Western world by the topographer Petrus Gyllius in the mid-16th century. Among its most famous features are two Medusa head reliefs used as column bases in the northwestern corner, which serve as exceptional examples of Roman sculpture and are shrouded in mythological legend. Following its most extensive restoration by İBB Miras, the cistern reopened in 2022 as a contemporary museum and cultural space, blending its deep historical memory with modern art and exhibition capabilities.
