# Basilica Cistern audio guide, five stops, free. 336 marble columns, each nine metres tall, hold up a sixth-century brick roof about 138 by 65 metres under the streets of Sultanahmet. Five of its stories play here; for the rest, photograph a column or a capital and ask Chiaro where it came from. Made by Chiaro. Not affiliated with Yerebatan Sarnıcı. Page: https://chiaro.ai/landmarks/basilica-cistern/ Start this self-guided Basilica Cistern audio guide in daylight, at the Milion: the marble stump at the northern corner of the Hagia Sophia square that once measured every road in the empire, with the cistern lying beside it under the street. From there you go down the stone stairs on the cistern's south-east side for the first view along the rows of columns, then walk the steel walkway through the body of the cistern, looking up at the capitals and brick vaults, stopping at the carved Hen's Eye column, and finishing at the two Medusa heads in the far north-west corner. About nine minutes of listening, and well under two hundred metres of walking underground. We went through every name, date and measurement here on 1 October 2026, comparing the English and Turkish Wikipedia articles with the history the cistern's former operator published, and we keep each practical fact filed next to the sentence it rests on, which is how we learn when it moves. The cistern is now run by the General Directorate of Foundations (vgm.gov.tr), and it decides the opening hours and the admission. Staff at the stairs and notices on site outrank anything written here; if they differ, follow them and drop us a line. ## The stops ### 1. The Milion, the empire's zero mile, beside the cistern Erected under Septimius Severus; rebuilt as a domed double arch under Constantine I; Ottoman water tower (suterazi) beside it · Third century AD, remodelled after 330; fragment found and re-erected 1967–68 · Marble: a single fragment, re-erected as a pillar, of a domed tetrapylon on four arches, the zero point of the empire's road distances · At the northern corner of Ayasofya Square, by the cistern, on the street and before any ticket Audio: https://audio.chiaro.ai/landmarks/basilica-cistern/en/milion.mp3?v=957587 (120 s) Look for: - The single marble pillar in its sunken, walled pit: the one fragment found in 1967–68 of the domed arch from which the empire's road distances were measured. - The tall rubble-stone tower behind it, the Ottoman suterazi or water tower. Its building, with the enlarged aqueduct, is why the Milion disappeared. - Hagia Sophia across the square. The Stoa Basilica's colonnaded gardens faced it, on the ground over the cistern. Look for a single battered pillar of pale marble standing in a sunken, walled pit at the corner of the square, with a tall tower of rough stone right behind it. It does not look like much. For a thousand years it was the point from which the whole Eastern Roman Empire measured its roads. This is what is left of the Milion. Septimius Severus put up the first version in the third century, when the city was still called Byzantium, and when Constantine re-founded it as his new capital in 330 it became the empire's zero-mile marker. Distances to the main cities of the empire were cut into its base. Constantine knew the Golden Milestone in the forum of Rome and wanted one of his own, only grander: a double triumphal arch on four great arches with a dome on top, and on the dome statues of himself and his mother Helena, a cross between them, looking east. Emperors kept adding to it. Justinian, the man who built the cistern you are about to walk into, gave it a sundial. In the eighth century its vaults were painted with the councils of the Church, and during Iconoclasm Constantine the Fifth had those replaced with scenes from the Hippodrome, which tells you something about his priorities. It survived the sack of 1204 and the conquest of 1453, and then, early in the sixteenth century, it simply went. The tower behind it is part of the reason. That is a suterazi, an Ottoman water tower, literally a water scale, and when the nearby aqueduct was enlarged and the tower went up, the Milion came down. So the city's water, which is the whole story of the place beneath your feet, finished off its most famous signpost. Nobody knew exactly where it had stood until 1967, when the houses on top were demolished and archaeologists dug. They found foundations and this one fragment, and they could name it because it lay beside a bent Byzantine water channel that follows the angle of the Mese, the main street of Constantinople, which began right here. Now look across at Hagia Sophia. Before Justinian's cistern, this ground was a great public square, the Stoa Basilica, with gardens inside a colonnade that faced the church, and the Imperial Library stood here until a fire in 475. The cistern takes its name from that square, and it lies right beside you, under the street. The street takes its name from the cistern in turn: Yerebatan, underground. ### 2. The first view: twelve rows of twenty-eight columns Byzantine builders for the Emperor Justinian I · 532 to about 542 · Brick vaults on 336 marble and granite columns, each 9 m high; the chamber about 138 by 65 m · At the foot of the stone stairs on the south-east side, where the walk into the cistern begins Audio: https://audio.chiaro.ai/landmarks/basilica-cistern/en/the-first-view.mp3?v=980575 (123 s) Look for: - The row straight ahead. Count columns towards the far wall, then remember there are twelve rows like it, 336 columns in all. - The floor under the shallow water: sixth-century Byzantine brick, uncovered only in the 2020–22 restoration. - The reflections. With only a little water kept in the cistern, the vaults and capitals are doubled in it. At the bottom of the stairs, give your eyes a minute. What they are adjusting to is a forest: marble columns in rows, each nine metres tall, each capped with a capital and a brick arch, running away from you into the dim, with a skin of still water beneath them doubling every one. There are 336 of them, in twelve rows of twenty-eight. The chamber they hold up is about 138 metres long and 65 wide, close to ten thousand square metres, enough to store 80,000 cubic metres of water. A German archaeologist, Eckhard Unger, measured it during the First World War and made it 138 by 64.6. Justinian had it built from 532, over roughly a decade, as the water store for the Great Palace of the emperors. Historical texts claim that seven thousand enslaved people worked on it. The water came from the Belgrad Forest, nineteen kilometres north of the city, by way of aqueducts that included the Valens Aqueduct. Then, for outsiders at least, it slipped out of memory. After 1453 it served Topkapı Palace for a while, and later the neighbourhood that grew up on top of it. People lowered buckets through wells in their houses and thought nothing of it. The man who put it back on the map was a French naturalist, Petrus Gyllius, sent to Constantinople in the 1540s by King Francis the First to hunt for ancient manuscripts. He measured the room, counted the columns, exactly 336, and had himself rowed between them, watching fish swim in the water under the boat. That is the origin of the Turkish name, Yerebatan Sarayı, the sunken palace: columns rising out of water, as far as a lamp could reach. When the city cleaned it out between 1985 and 1987, more than 50,000 tons of silt came out, the boats gave way to walkways, and on 9 September 1987 it opened as a museum. Now look down through the water beside it. That brick floor is the one Justinian's builders laid. For decades it was buried: the 2020 to 2022 restoration broke out about 1,440 cubic metres of mid-twentieth-century concrete and 1,600 of sediment to reach it. The cistern is kept with only a little water now, and that thin sheet over sixth-century brick is what turns the whole room into its own reflection. ### 3. Looking up: the capitals and the brick vaults Byzantine builders for Justinian I, reusing columns from older buildings; repaired in 1723 by the architect Muhammad Ağa of Kayseri · 532 to about 542; repairs 1723, under Abdulhamid II, 1968, 1985–87 and 2020–22 · Brick cross-vaults on arches, carried by columns 9 m high set about 5 m apart · On the walkway, in the body of the cistern, looking up between the rows Audio: https://audio.chiaro.ai/landmarks/basilica-cistern/en/vaults-and-capitals.mp3?v=975350 (122 s) Look for: - The capitals. Find a leafy Corinthian one, then a plain uncarved block next to it: the mismatch is the sign of recycled columns. - The brick in the vaults, laid in rings and chevrons that close towards the middle of each bay. - The thin steel rods running between the capitals, with star-shaped plates where they meet the stone. They went in during the 2020–22 restoration, against earthquakes. Stop anywhere along the walkway and tip your head back, because the best thing in here is the part almost nobody photographs: the tops of the columns. Pick one capital, then look at its neighbours. A leafy Corinthian one, all curling acanthus; beside it a plain block with no carving at all; further on a scrolled Ionic top. They do not match because they were never meant to. Most of these columns were recycled from ruined buildings and brought to Constantinople from around the empire, along with the columns that went into Hagia Sophia, and they are cut from different marbles and granites. Only 98 of the 336 were made for this room. The rest are second-hand, which makes the cistern one of the great salvage yards of the ancient world, put to work holding up a roof. The roof itself is brick. The builders dug down to bedrock beneath the courtyard of the imperial stoa, stood the columns in rows about five metres apart, joined them with arches, and closed each bay over with a brick vault. Follow the courses of brick and you can watch them turn in rings and chevrons towards the middle of every bay. The brick walls and the brick floor were then sealed with a thick mortar made from Horasan lime, to keep the water in. Now find the thin steel rods running from capital to capital, with star-shaped plates where they meet the stone. Those are new. The old iron tie-rods had corroded, and in the restoration of 2020 to 2022 they were swapped for stainless-steel rods to help this room ride out an earthquake. The same work cleaned salt crystals and biological growth off the marble and the brick, and stripped away a fifty-centimetre cement render added in the mid-twentieth century. That was only the latest in three centuries of patching. The first Ottoman repair came in 1723, under Sultan Ahmed the Third, by the architect Muhammad Ağa of Kayseri; the second came under Abdulhamid the Second. Between 1955 and 1960 nine columns in danger of collapse were wrapped in a thick coat of concrete, and in 1968 cracked masonry and damaged columns were mended again. Which leaves the question of why a water tank got Corinthian capitals at all. The honest answer is in front of you. The columns were there to be had, the capitals came with them, and nobody expected them to be looked at. For centuries the only people who saw them were the ones rowing through with a lamp. ### 4. The Hen's Eye column Late Roman stone carvers; reused by Justinian I's builders · Late Roman; its carving resembles the columns of the Arch of Theodosius I (379–395); reused 532 to about 542 · Marble column carved in relief with eyes, slanting branches and tears, 9 m high like its neighbours · On the walkway, in the body of the cistern, among the ordinary columns Audio: https://audio.chiaro.ai/landmarks/basilica-cistern/en/hens-eye-column.mp3?v=749861 (94 s) Look for: - The rings carved like eyes, each with a tail running down the shaft like a tear. - The slanting branches carved in raised relief between them. - Its plain neighbours, carrying the same vault with no decoration at all. Keep your eyes on the columns as you walk, because among hundreds of plain shafts there is one that looks as if it is weeping. When a column comes up carved from top to bottom, stop there. Look closely at the pattern. Rings like eyes, each with a tail running down from it like a tear, and slanting branches between them, all carved in raised relief right up the shaft. The name that has stuck to it is the Hen's Eye, and the drops are read as tears. It is the same height as every other column in here, nine metres, and on its own it would be a handsome piece of late Roman carving. Down here, in a room built only to hold water, it is a stray. It was not made for a cistern. It closely resembles the columns of a triumphal arch that the Emperor Theodosius the First, who reigned from 379 to 395, put up in the Forum Tauri, the great square of the city that is now Beyazıt. Whether this column came from that very arch is not recorded. What the likeness does tell you is how Justinian's builders worked. They needed 336 columns, and they took them where they found them: from ruined buildings, from around the empire, from monuments whose emperors had been dead for well over a century. That habit explains the look of the whole room. Most of the columns around you are plain cylinders; a few are angular or fluted; one is covered in eyes. They were there to hold up a roof, and whatever was carved on them simply came along. The 2020 to 2022 restoration gently cleaned the marble here of biological growth and salt. Put your face level with one of the eyes and follow its tear down the stone to the next ring. Then look at the columns beside it, which carry the same vault and the same weight with no decoration at all, and you have the whole cistern in one glance: a single triumphal column doing the same job as three hundred working ones. ### 5. The two Medusa heads in the north-west corner Late Roman sculptors, unnamed; reused as column bases by Justinian I's builders · Late Roman; reused 532 to about 542; uncovered 1985–87 · Two carved marble blocks, one upside down and one on its side, under two of the cistern's 9 m columns · The north-west corner of the cistern, at the far end of the walkway from the stairs Audio: https://audio.chiaro.ai/landmarks/basilica-cistern/en/medusa-heads.mp3?v=881309 (110 s) Look for: - The upside-down head: chin at the top, hair spread along the floor. - The second head, turned on its side under the other column. - The carved pedestal block sitting on top of the upside-down head, a separate piece between Medusa and the column shaft. This walk ends in the north-west corner of the cistern, at the foot of two columns, with what most people came down the stairs to see: two huge stone faces of Medusa, one set upside down and the other lying on its side. Start with the upside-down one. The chin is at the top and the hair spreads out along the floor. In Greek myth Medusa was one of three Gorgon sisters, and whoever met her eyes was turned to stone. A separate carved pedestal block sits on top of her, and the column rises from that. Then find the second head, turned on its side under the other column. Nobody knows where they came from. They are thought to have been taken from a late Roman building, and the stone is said to come from the quarries of the island of Proconnesus. There is no evidence that either block was a column base before it arrived here. Nor were they on show. They were only uncovered in the great clean-out of 1985 to 1987, when more than 50,000 tons of silt came out of the cistern. So why upside down and sideways? There are three stories. One says the builders turned her on purpose, so that her gaze would lose its power down here. One says it is plain reuse: a block of the right size, laid whichever way it fitted, the angles an accident. The third reads a message into it, the old pagan image overturned by a Christian city. None of them can be proved, and there is something right about the most famous thing in the cistern being the one nobody can explain. The room does not quite end here, either. Forty-one columns in an area on this north-west side were closed off under Abdulhamid the Second and cannot be seen today, so what you have walked through is not the whole of it. The heads have travelled a long way without moving. Dan Brown put the cistern and its inverted Medusa into his 2013 novel Inferno, and the showdown of the 2016 film is set down here. But the film was not shot here: a full-size copy of the cistern was built on a set in Budapest, so that the real one would come to no harm. The face in front of you is the original, and she has been standing on her head since the sixth century. ## Before you go Sultanahmet, in the Fatih district of Istanbul: the cistern lies 150 metres south-west of Hagia Sophia, under Yerebatan Caddesi, beside the Milion at the northern corner of the Hagia Sophia square. Inside, the stone stairs go down on the south-east side. Stop one is the Milion itself, up on the street. Tram line T1 has a stop called Sultanahmet, between Gülhane and Çemberlitaş. Stop one waits at the northern corner of the square of Hagia Sophia, by the Milion. - The operator, the General Directorate of Foundations, sets the opening hours and the admission. Check both at the entrance on the day you go. - Listen to stop one up on the street, before the stairs. It is at the Milion, beside the cistern, and needs no ticket. - Follow the walkway from the south-east stairs towards the north-west: the Medusa heads are at its far end, the farthest point from the stairs. The General Directorate of Foundations, which runs the cistern, has not published an official audio guide or a price for one, so ask at the entrance whether a guide is offered. These five stops need nothing but your phone's browser, from the pavement by the Milion to the Medusa heads, and every narration sits written out beneath its player, handy in the half-light when you would sooner read than listen. Official site: https://www.vgm.gov.tr/ ## Questions **Is there a free Basilica Cistern audio guide?** This page is one: five stops, starting up on the street at the Milion and ending under the Medusa heads, played in your phone's browser, with every word of each stop written out below its player. Anything the walk passes by, a capital or a column or a patch of Ottoman repair, photograph it and ask Chiaro what it is. **Can I listen to the Basilica Cistern audio guide without a ticket?** The first stop, yes. It stands at the Milion, on the street at the northern corner of the Hagia Sophia square, beside the cistern. The other four are underground, beyond the entrance, and admission there is set by the operator, the General Directorate of Foundations, so check it at the entrance. **How much is the official Basilica Cistern audio guide?** The General Directorate of Foundations, which runs the cistern, has published no official audio guide and no price for one; ask at the entrance whether a guide is offered. Listening to these five stops is free. **Where are the Medusa heads in the Basilica Cistern?** In the north-west corner, at the foot of two columns, at the far end of the walk from the stone stairs on the south-east side. One head is set upside down and the other on its side. Both were uncovered in the clean-out of 1985 to 1987. **Where should I start the Basilica Cistern walk?** Above ground, at the Milion: the lone marble pillar in a sunken pit at the northern corner of the Hagia Sophia square, beside the cistern. Play stop one there, then go down the stone stairs on the south-east side and follow the walkway north-west through the columns. ## Continue in the app Point Chiaro at anything at the Basilica Cistern. Five stops cover a handful of the 336 columns, and every one of the others has a history of its own: a capital salvaged from some ruined building, a shaft cut from a different marble, a repair made in 1723. Hold up your phone to whichever one catches the light and ask. Chiaro names the stone, guesses honestly at where it was quarried or pillaged, points you to the next thing worth a look, and goes on answering down the whole length of the walkway. Download Chiaro: https://apps.apple.com/app/apple-store/id6745618830?pt=127817940&ct=basilica-cistern-md&mt=8