Basilica Cistern

Interesting facts

1. 1

   Most of the 336 columns were scavenged from demolished ancient buildings, explaining the variety of styles including Ionic and Corinthian.

2. 2

   The two Medusa heads supporting columns were likely placed upside down or sideways to negate the mythological power of her gaze.

3. 3

   The cistern was known as the 'Sunken Palace' due to the reflection of the columns in the water.

4. 4

   It was rediscovered in the 16th century by Petrus Gyllius, who observed locals drawing water through holes in their floorboards.

5. 5

   The water was originally transported via the Valens Aqueduct from the Belgrade Forest, 19 kilometers away.

6. 6

   The structure remained largely unknown to the Western world until the Ottoman era.

7. 7

   The brickwork uses a specialized hydraulic mortar that remains resilient after 1,500 years.

8. 8

   Modern lighting was installed to emphasize the textures of the masonry and the shadows created by the columns.

Overview

The Basilica Cistern is a massive 6th-century subterranean reservoir built under Emperor Justinian I to serve the Great Palace of Constantinople. It covers 9,800 square meters and features 336 marble columns, mostly reclaimed from older temples and structures. The cistern utilizes a unique grid of 12 rows of 28 columns spaced approximately 4.8 meters apart. It is constructed with high-quality brick vaults and mortar lining to ensure waterproofing. Recent restoration efforts have reinforced the vaulting, cleaned the sediment-filled floor, and installed dynamic lighting systems. The cistern remains a functional feat of Roman engineering, capable of holding up to 80,000 cubic meters of water. Walkways now hover above the water level, allowing visitors to traverse the space safely. Two large Medusa head blocks serve as column bases, sourced from earlier Roman-era architecture. The site is currently fully open to the public following extensive structural upgrades.

Insider tips

• Wear comfortable, slip-resistant shoes as the ground can be damp and uneven.

• Allow your eyes to adjust to the dim, moody lighting for several minutes after entering.

• Visit during the shoulder seasons to avoid the peak volume of cruise ship crowds.