The Beneath Istanbul's busy streets lies a hidden world—a forest of marble columns rising gently out of calm water. Welcome to the Basilica Cistern, a relic from the Byzantine era that's survived for over 1,500 years. Exploring this ancient cistern isn't just stepping into history—it’s discovering the layers of its fascinating past. Let's dive right in and uncover why this cistern exists, what happened to its namesake Basilica, and the mysterious stories behind its treasures.
Recommended tickets to Basilica Cistern
History of water cisterns in Istanbul
The ancient city of Constantinople (modern-day Istanbul) had no major rivers nearby. To survive — especially during sieges — the Byzantines built a network of massive underground cisterns fed by aqueducts from distant forests like Belgrad.
Today, there are hundreds of these cisterns underneath the city — some discovered, many still hidden. Some, like the Binbirdirek Cistern and Theodosius Cistern, have been restored and are open to visitors. But none are as grand or atmospheric as the Basilica Cistern, which stands out with its 336 marble columns and a capacity to hold 80,000 cubic meters of water.
These structures weren't just practical; the Byzantines reused many architectural pieces from earlier Roman buildings—a detail that'll matter when we talk about the Medusa heads below.
Basilica Cistern History: Timeline of events
- 3rd–4th century AD: The Romans built the Stoa Basilica—a busy market square.
- AD 476: A huge fire destroys the Stoa Basilica.
- AD 532: Emperor Justinian I constructed the Basilica Cistern underneath this ruined plaza to provide fresh water for the Great Palace.
- 9th–13th centuries: Continues serving Byzantine Constantinople during times of peace and siege.
- AD 1453: The Ottomans conquer Istanbul. The cistern waters the gardens of the Topkapı Palace briefly but eventually falls into neglect and obscurity.
- 1545: French scholar Petrus Gyllius rediscovers the cistern while exploring Byzantine ruins. Locals were still fishing from the cistern via holes in their basements!
- 1985–1987: A massive cleanup removes 50,000 tons of sludge. Walkways are installed for visitors.
- 1987: Opens to the public as a tourist attraction.
- 1996 onward: Gains global fame by appearing in movies like From Russia with Love, The International, and Inferno.
What happened to the original Basilica?
The cistern got its name from the old Stoa Basilica, a vibrant gathering and commercial spot in ancient Roman Constantinople. After the fire in 476 AD, the basilica above ground vanished without a trace.
But the people never stopped referring to this underground masterpiece by its old name—Basilica. Even though you won't see the original structures on the surface today, the cistern keeps the memory of that Roman hub alive underground.
The curious case of the Medusa heads
If there's one thing visitors always ask about, it's those two huge Medusa heads staring back mysteriously from their quiet corner. Even more puzzling, one is placed sideways, and the other is upside-down—why?
The truth is, nobody knows exactly where these Medusa heads came from. Modern research suggests a few possibilities:
- They could be fragments of a Doric temple dedicated to Athena — fitting, given Athena and Medusa’s mythological rivalry.
- They might have belonged to a triumphal arch built for Constantine the Great.
- Some believe they were part of the Stoa Severiana, another key ancient building in Istanbul.
Experts believe their odd positioning is due simply to convenience, rather than hidden symbolism. Builders likely grabbed these strong artistic blocks from ruins for practical reasons.
Fun fact: there's a third double-headed Medusa block preserved at the Istanbul Archaeological Museum, showing similar craftsmanship to the ones in the cistern.
In recent years, scholars have digitally scanned the Medusa heads using photogrammetry, creating 3D models and virtual reconstructions of what the original structures might have looked like. These reconstructions suggest that these heads once adorned monumental Roman or Byzantine architecture.
Recent history and cultural revival
After a massive restoration in the 1980s, Basilica Cistern opened its doors again in 1987, captivating everyone who visited. Soft lighting and atmospheric beauty transformed it into Istanbul’s underground cathedral.
Today, you can explore one of Istanbul's top attractions, known globally from movie appearances:
- From Russia with Love (1963) — James Bond navigates through its waters.
- The International (2009) — Adds suspense to a high-stakes scene.
- Inferno (2016) — Brings the cistern’s haunting mystery to a global audience.
