The Basilica Cistern is the largest underground reservoir surviving in Istanbul and one of the most surprising visits in Sultanahmet, because you can't see it from the street. You go down a staircase and find yourself in a hall of 336 columns reflected in the water, ten degrees cooler than outside.
Justinian had it built in the sixth century to supply the Great Palace, and for centuries the people of Istanbul forgot it was there. Today it's a fixture of any first day in Istanbul, a short walk from Hagia Sophia.
A little history
It was built around 532, after the Nika riots, on the site of an earlier basilica that gives it its name. It measures about 140 metres long by 65 wide and could hold tens of thousands of cubic metres of water, brought by aqueduct from the Belgrade Forest. The columns, around nine metres tall, were taken from older temples and buildings, which is why no two capitals are alike.
After the Ottoman conquest it fell out of use and its existence was forgotten. It was rediscovered in the 16th century by the French traveller Petrus Gyllius, who noticed locals drawing water — and even fish — with buckets from their basements. It opened to the public in 1987, and between 2017 and 2022 it underwent a thorough restoration: the columns were reinforced, the water level was lowered, and today's lighting and walkways were installed.
What to see in the Basilica Cistern
The forest of columns
Twelve rows of 28 columns, almost all marble, with a mix of Corinthian and Doric capitals. With the low light and still water, it feels like a sunken temple. The restoration drained some of the water, so you now get a better view of the bases and the brick joints.
The Weeping Column
Near the entrance stands a column carved with teardrop or peacock-eye motifs. Tradition links it to the workers who died during construction. It's the one everybody touches on the way past.
The two Medusa heads
At the end of the route, in the north-west corner, two columns rest on Roman-era Medusa heads, one turned on its side and the other upside down. Nobody knows where they came from; the likeliest explanation is that they were reused blocks placed that way to fit, although romantic guidebooks prefer the theory that it cancels out the Gorgon's gaze.
The art installations
Since the reopening, contemporary sculptures have been placed among the columns, such as a large hanging jellyfish and figures rising out of the water. Not everyone likes them; I think they give the space a sense of scale.
Tips for your visit
Allow 45 minutes. It's a one-way route along metal walkways, with no stairs apart from those at the entrance and exit.
- Any time of day works, as there's no natural light, but the ticket queue is shorter first thing in the morning and in the last hour before closing.
- The floor can be damp and water drips from the ceiling: nothing dramatic, but mind your phone.
- The lighting changes colour; if you want natural-looking photos, wait for the amber tone.
- For visitors with reduced mobility: the entrance and exit are staircases, and there is no lift.
Tickets and prices
At the time of writing (2026 rates), a daytime ticket costs 1,950 Turkish lira, about €35. There's an evening session, with different lighting and fewer people, which is ticketed separately: 3,000 lira, about €53. On my tours, tickets are either included or bought by the guide, so there's no ticket queue for you.
How to get there
The entrance is on Yerebatan Street, opposite Hagia Sophia and two minutes from the Hippodrome. The Sultanahmet tram stop is a few steps away.
How we visit it on my tours
On the classic Istanbul day tour we go in after Hagia Sophia, when the contrast between the daylight outside and the half-light inside is greatest. On multi-day programmes such as Essential Istanbul we save it for the first day, and if you'd like to see it by night, I can include it in an evening walk around Istanbul.
Tell me how you'd like your trip to be in plan your tailor-made trip and we'll fit it in.