Basilica Cistern

Constructed in the 6th century by Emperor Justinian I, the Basilica Cistern is the largest of several hundred ancient cisterns beneath Istanbul. It was built using the labor of 7,000 slaves and was designed to provide water filtration for the Great Palace of Constantinople and other buildings on the First Hill. Its name derives from the Stoa Basilica, a large public square that once stood above it, emphasizing its central role in the city's infrastructure. The structure is a masterpiece of Byzantine engineering, featuring 336 marble columns arranged in 12 rows. Many of these columns were salvaged from older Roman temples, a practice known as spolia, which explains the variety in their styles and capitals. The most famous of these are the two Medusa heads used as column bases at the northwestern edge, which remain one of the city's most enduring mysteries and popular photographic subjects. After the Ottoman conquest in 1453, the cistern continued to provide water to Topkapi Palace but eventually fell into disuse and was forgotten by the authorities. It was rediscovered in 1545 by the French scholar Petrus Gyllius, who noticed locals catching fish through holes in their basement floors. Today, following a massive restoration completed in 2022, it serves as a breathtaking museum and art space, enchanting visitors with its atmospheric lighting and acoustics.