A dark fortress that time forgot is rising from the ruins of empires

A 19th-century engraving by Augustin François Lemaitre and Jean-Baptiste Arnout, from "Historia de Turquia" by Joseph Marie Jouannin and Jules Van Gaver. (PHAS/Universal Images Group Editorial/Getty Images via CNN Newsource)

ISTANBUL -- It’s been a prison, a fortress, an imperial treasury, and a desolate ruin. Over hundreds of years, Istanbul’s dark citadel has survived empires and neglect alike — and now, as it undergoes a major rebirth, its deepest secrets are coming to light.

Yet despite being one of Istanbul’s most historically important landmarks, Yedikule Hisari, or “Fortress of the Seven Towers,” still receives just a fraction of the visitors of other touristic big-hitters such as Topkapi Palace or the Basilica Cistern.

That’s slowly starting to change thanks to a multi-stage restoration project which began in 2020.

Yedikule’s history begins 1,700 years ago, when Constantine the Great declared the city then known as Byzantium the new capital of the Eastern Roman Empire and renamed the settlement Constantinople in his own honor.

The fourth-century Walls of Constantinople were one of the world’s most elaborate, and successful, defense systems ever built and a section bordering the Sea of Marmara survives at Yedikule today.

Built into the fortress’s western walls is the Porta Aurora, or Golden Gate, a 39-foot-high triple triumphal arch made of Proconnesian marble, flanked by towers on either side, which was the ceremonial portal through which Byzantine emperors set off on campaigns and made their (sometimes) triumphant returns.

A statue of four enormous elephants pulling a chariot once overlooked stately gilded doors while bronzes, including those of Emperor Theodosius and the goddess Nike, adorned it.

Nowadays, the gate is bricked up and entrance through the walls is a simpler matter than in the past when an army was required to lay siege.

A 400-lira entrance fee (around US$8) gets you inside the star-shaped fort and its vast central courtyard.

The yard is often used as a concert venue and as an outdoor cinema, but empty of the hustle and bustle of visitors here to enjoy music and movies, it’s a rather bleak space.

A legacy of two empires

It takes imagination to see it as it was after Constantinople was conquered by the Ottoman ruler Sultan Mehmed II, who in 1458 commissioned the building of the fortress using the old city walls.

For four centuries, says tour guide Turan Oflaz, it was “a vibrant centre of life” housing a large military barracks, a mosque, water wells, two Christian chapels and a school.

In the 19th century it even housed an aslanhane, or lion house, for big cats previously kept at Topkapı Palace, the home of the sultans and imperial family.

No trace of the chapels, the school or the lions can be seen today. Only a minaret from the 15th-century mosque remains, incorporated into a new structure, and a stone path cutting across the space.

This pathway not only dissects the courtyard, it splits time.

“The path we walked from the entrance gate of the fortress to the mosque,” Oflaz says, “has remnants of a 600-year-old Ottoman road” while the path from the mosque onwards “was a 1,600-year-old Roman road, making Yedikule the “shared heritage” of two great empires.

It’s not known whether the Golden Gate “was built by Theodosius I at the end of the 4th century or by Theodosius II around the middle of the 5th,” says historian Hayri Fehmi Yilmaz, but the addition of four towers and a triple barrier defense system with moat, in an upgrade that saw Constantinople invulnerable to enemy attacks for hundreds of years, is definitively attributed to his grandson Emperor Theodosius II.

Sultan Mehmed II went on to add three new towers and also walls to the fortress, enclosing the space. “The structure, formed by the combined walls of the Byzantine and Ottoman periods, represents both civilizations as a whole,” says Yilmaz.

An Ottoman Aladdin’s cave

Although it’s called a fortress, it was built to protect the wealth of the empire.

Sultan Mehmed II used Yedikule “as a strategic centre where the Imperial Treasury and important state archives were kept, says Oflaz. In this respect, “the fortress acted as the ‘central bank’ and the most secure vault” of the Ottoman Empire.

Some sources claim each tower contained a specific treasure, while others suggest they were all locked in the Treasury Tower. Its approximately 10-foot-thick walls, watched 24/7 by a Janissary unit, the sultan’s own infantry corps, were ideal for safekeeping.

Inside, says Yilmaz, were valuable items brought to Constantinople from campaigns in Persia, Syria and Egypt, including “precious swords, shields, bows, quivers, all kinds of war implements,” as well as “saddles and harnesses for horses, precious books and bindings.”

The treasury was moved to Topkapı Palace in the 16th century and Yedikule then became a prison. Its towers housed a veritable United Nations of nobles and ambassadors from countries such as Poland, Russia, France and Hungary as well as Turkiye, inside its grim, impenetrable walls.

History written in stone

Kitabeli Kulesi, the Tower of Inscriptions, sits directly opposite the Golden Gate.

Despite its romantic-sounding name, it was a prison where inmates could languish for months in tiny rooms oppressed by near darkness, awaiting release or death.

Christians and other foreigners were held here, such as consuls, the Ottoman-appointed Princes of Samos, Venetians, Armenians and Russians, including Ambassador Pyotr Andreyevich Tolstoy, ancestor of the more famous Leo.

They left “inscriptions carved into the stone walls,” says Oflaz, making Kitabeli Kulesi “virtually a centre of diplomatic memory.” Written in Latin, Hungarian, French, Italian and many other languages, the inscriptions “generally contain the names of the prisoners, their hometowns, the dates of their imprisonment, and sometimes,” Oflaz adds, “their grievances against life.”

During the 16th and 17th centuries, many of the inmates were Hungarian and Polish. At the time Poland and the Kingdom of Hungary were the most powerful and strategic rivals of the Ottoman Empire and numerous battles were fought over borders.

Enemy captives would be brought to Istanbul and incarcerated in Yedikule where they became “powerful political pawns in diplomatic negotiations,” says Oflaz, used “to protect military secrets and safeguard state interests by returning them for high ransoms when necessary.”

Essentially, they were diplomatic bargaining chips.

A dark past and a bloody well

Some prisoners made it home in one piece while others met a grisly end inside the fortress walls.

One of the more notable victims was David Komnenos, the last king of Trebizond (modern-day Trabzon in northeast Turkiye). After his Black Sea stronghold fell to Mehmed II in 1461, the king, says Yilmaz, “was captured and exiled to the Balkans with his family. In 1463, he was summoned to Istanbul” on suspicion of plotting with foreign allies. Once there, he was executed, along with his three sons and other relatives. “With this execution,” Yilmaz explains, “the last known member of the Byzantine dynasty died and it’s said they were buried in the moats in front of the city walls.”

An even more gruesome case is that of Constantin Brâncoveanu, the prince of Wallachia (in modern-day Romania). He’d long managed to navigate shifting alliances between the various powers until Sultan Ahmed III called his loyalty into question. Brâncoveanu and his family were brought to Yedikule in 1714 where they were tortured. When they refused to recant and convert to Islam, the prince and his four sons were beheaded and their bodies thrown into the Sea of Marmara.

According to popular myth, there’s a well in Yedikule linked to the sea by a secret passage. As the story goes, it’s where the heads of slain prisoners were thrown to be carried away on the tide. Known as Kanlı Kuyu, the Bloody Well, many believe it was inside the Tower of Inscriptions but Yilmaz insists, “its location is unknown. There is no well inside the Tower of Inscriptions.” However, there is a “magnificent well dating back to the 15th century in front of the Treasury Tower” and “another near the Golden Gate where most Muslim prisoners were confined.”

This is where Oflaz believes the well was housed, inside the structure now known as Genç Osman Kule, the southernmost tower flanking the Golden Gate. It’s named for Osman II, Genç or “Young,” Osman. Aged only 14 when he took over the Empire in 1618, he was one of the youngest Ottoman Sultans. Three years into his rule he led an unsuccessful campaign against Poland and blamed the Janissaries who’d become focused on their independence rather than following orders and keeping their ruler safe.

Osman was determined to bring the Janissaries back under his control. When the Janissaries found out, he was deposed then briefly held in Yedikule before tragically being, in Oflaz’s words, “martyred in his cell during the events known in history as the ‘Young Osman Incident’.” Ironically, one of young Osman’s assassins, grand vizier Kara Davud Pasha was himself executed at Yedikule after losing his power.

There’s more to life than death

Not everyone detained at Yedikule had as grim a fate. Many foreign prisoners had considerable freedom, says Yilmaz and could “move freely within the fortress and even stay in houses in the surrounding neighborhood.”

Some even managed to wander through the city and up the Bosphorus as far as the Black Sea, like François Pouqueville. Pouqueville was one of Napoleon’s emissaries and he ended up being imprisoned in Yedikule from 1799 to 1801.

He “not only survived his nearly two-year imprisonment in Yedikule” says Oflaz, “but also transformed this period into a time of immense intellectual growth,” spending his days corresponding with his people in France and working on literary endeavours. “As a medical doctor, he took on the treatment of the soldiers in the fortress,” taught himself vernacular and “Ottoman Turkish” and, says Oflaz, “thanks to his contacts with the Greeks in Istanbul, he also perfected his knowledge of Modern Greek.”

A new story begins

By the middle of the 20th century Yedikule’s dark past was largely forgotten and it was best known as a location used by Yeşilçam, the mid-century cinema boom that was Turkiye’s answer to Hollywood. However by the mid-1970s Yeşilçam and the fortress were both in decline, gaining a reputation as a dumping ground for trash.

With its restoration, says Oflaz, waxing lyrical, Yedikule has regained its rightful place as “Istanbul’s mühür.” Mühür were the special seals used by Ottoman sultans to stamp and secure their correspondence and for him, Yedikule is the signature of Istanbul.

Standing atop the Golden Gate he declares, “On one side I have the noise of the modern world, and on the other, a silence that has lasted fifteen hundred years. Looking at Istanbul from here is like breathing in the splendor of Rome, the aesthetics of Byzantium, and the power of the Ottomans, all at once.”

By Lisa Morrow, CNN