On the southern edge of Istanbul`s historic peninsula, where the majestic Theodosian Walls meet the waters of the Sea of Marmara, stands one of the city`s most impressive fortresses — Yedikule, which means "Fortress of Seven Towers." This fortification blends the architectural traditions of two great empires — Byzantine and Ottoman — and its walls preserve the memory of a millennium of Constantinople-Istanbul`s history.
Yedikule Fortress is located in the European part of the city, in the Fatih district, not far from the coast of the Sea of Marmara. Its monumental towers are visible from afar, and even today, despite years of restoration, they leave an indelible impression on every visitor.
The Golden Gate: Legacy of the Byzantine Emperors
The history of Yedikule Fortress begins long before the arrival of the Ottomans. At the end of the 4th century AD, around 390, Emperor Theodosius I the Great ordered the construction of a triumphal arch that was to serve as the ceremonial entrance to Constantinople. Later, under Emperor Theodosius II, when the famous Theodosian Walls were built, the arch was incorporated into the city`s fortification system and named the Golden Gate.
The Golden Gate was the largest and most impressive gate of the Byzantine capital. It reached a height of 15 meters and was clad in marble brought from the islands of the Sea of Marmara. In Roman times, the marble towers were adorned with gilded and bronze statues, and the gate leaves were covered with gold — hence their name. A bronze statue of the goddess of victory Nike was placed on the arch, along with a chariot drawn by elephants. A Latin inscription in golden letters read: "Theodosius adorned these places after the fall of the tyrant. He brought a golden age, building a gate of gold."
These gates were used exclusively for ceremonial occasions. They were opened only to welcome the emperor returning in victory, and triumphal processions passed through them. Via Egnatia, the famous Egnatian Way leading from Constantinople through the Balkans to Europe, passed through the Golden Gate.
Over time, as the Byzantine Empire weakened, the gate openings were walled up and reduced for better defense, and after the Ottoman conquest, their use ceased altogether. Today, you can see the surviving marble towers and pylons of the Golden Gate incorporated into the fortress, as well as holes in the stone where the golden letters and statues were once attached.
Ottoman Fortress: Seven Towers of Mehmed the Conqueror
Soon after the conquest of Constantinople, in 1457–1458, Sultan Mehmed the Conqueror ordered the transformation of the Golden Gate and the adjacent section of the wall into a powerful fortress. Three new, more massive towers were added to the four existing Byzantine towers, connected by high walls. This formed an enclosed pentagonal courtyard, and the total number of towers reached seven, giving the fortress its name — Yedikule.
Initially, the new Yedikule Fortress served as the treasury of the Ottoman Empire. Its towers housed the state treasury, valuable documents, archives, weapons, and gold and silver bullion. The Sultan well understood the importance of protecting these riches, and the fortress with its strong military garrison was perfectly suited for this task. However, in the 16th century, under Sultan Murad III, the treasury and archives were moved to Topkapi Palace, and Yedikule acquired a new, grim function.
The Main Prison of the Ottoman Empire
For more than three centuries, Yedikule Fortress served as a state prison, where the most important and dangerous prisoners were incarcerated. Ambassadors of hostile powers, political opponents of the Sultan, disgraced viziers, and representatives of overthrown dynasties ended up here. A harsh atmosphere prevailed, and the very name "Yedikule Zindanları" inspired terror.
Among the most famous prisoners and victims of the fortress were:
• David Komnenos, the last Emperor of Trebizond, executed here in 1463.
• Sultan Osman II, who at the age of 17 was imprisoned in Yedikule and brutally murdered by Janissaries during a revolt in 1622. The caftan in which he was killed is today preserved in the collection of Topkapi Palace.
• Constantine Brâncoveanu, the Voivode of Wallachia, executed along with his sons in 1714.
• The Russian diplomats Pyotr Andreyevich Tolstoy and Yakov Ivanovich Bulgakov, who were held here during the Russo-Turkish Wars.
During the Napoleonic Wars, many French prisoners were held in the fortress, including the writer and diplomat François Pouqueville, who spent more than two years here and left detailed descriptions of the fortress in his memoirs. The last prisoner was released from Yedikule only in 1837.
The Towers and Their Secrets of Yedikule Fortress
Each of the seven towers of Yedikule had its own name and purpose. The names of some have survived to this day:
• The Tower of the Ambassadors — foreign diplomats were held here, and Latin and German inscriptions-graffiti left by them can still be seen on its walls.
• The Tower of Osman — the place of imprisonment and death of Sultan Osman II.
• The Tower of Written Orders — where documents were probably stored.
The towers served not only as prison cells but also as warehouses, powder magazines, and defensive fortifications. The thickness of their walls, narrow embrasures, and gloomy dungeons still preserve the spirit of those harsh times.
The Inner Courtyard and Later History of Yedikule Fortress
Inside the fortress, in the center of the spacious courtyard, stood a small mosque with a fountain built by Mehmed the Conqueror, as well as garrison houses that essentially formed a separate city quarter.
In the 19th century, the appearance of the fortress changed significantly. In the 1830s, the prison was closed. For a time, lions from the Topkapi Palace menagerie were kept here, then gunpowder production was established, and later it became an ammunition depot. The residential houses were demolished, and a women`s art school was built in their place. Finally, in 1895, Yedikule was declared a museum.
Yedikule Fortress Today: Rebirth and New Life
In 2019, the fortress was transferred to the Fatih municipality, and large-scale restoration began. During archaeological excavations in the courtyard, unique finds were discovered: the original foundation of the Fatih Mosque and the oldest surviving Byzantine pavement of Constantinople, 1500 years old.
Today, Yedikule is open to visitors. In the summer, concerts and cultural festivals are held in the inner courtyard, for which an open-air amphitheater was built. Visitors can climb the walls and towers, from which a magnificent view of the Sea of Marmara and the surrounding area opens up.
Visitor Information for Yedikule Fortress
Yedikule Fortress is located at: Yedikule district, Fatih. You can get there by buses from Taksim or Eminönü, or by the Marmaray metro line to Kazlıçeşme station, from which it is about a 10-minute walk. The museum is open daily from 9:00 AM to 4:30 PM, except Wednesdays. Entrance is paid.
For connoisseurs of fortification architecture, Yedikule represents a true encyclopedia of the military architecture of two great empires. Here one can trace how approaches to the construction of fortifications changed over a millennium: from the elegant marble columns of the Byzantine triumphal arch to the stern, squat towers of the Ottoman period designed to withstand cannon fire. It is a rare example of how one era is built upon another, not destroying but complementing the preceding one.
