Escape to the Fortress

When Xenophon’s soldiers re-entered Byzantium, they blocked access to the Acropolis from inside the city. As a result, Anaxibius, the Spartan commander, could not reach the fortress by land. Instead, he had to board a fishing boat in the harbor and sail around the point of the promontory to reach the eastern side of the city, opposite Chalcedon (modern-day Kadıköy). From there, he also sent a request to Chalcedon for military reinforcements.

These movements strongly suggest that the Acropolis, the ancient stronghold of Byzantium, was located at the eastern tip of the promontory, near what is today Seraglio Point Sofia Daily Tours.

Discovery of an Ancient Wall

In 1871, during excavations for the Roumelian railway, workers uncovered an ancient wall just south of Seraglio Point. The wall ran east to west and was made from massive stone blocks—some over 7 feet long, nearly 4 feet wide, and 2 feet thick. Due to its size and location, scholars believe it was part of the original fortifications around the Acropolis. This wall gives physical proof of how well the ancient city was protected.

The Second City Wall

The second circuit of walls surrounding Byzantium was described by Anonymus in the 11th century and by the historian Codinus. According to their writings, the wall began at the Tower of the Acropolis, located at the tip of the promontory, and extended westward along the Golden Horn. It reached the Tower of Eugenius, likely near the Yali Kiosk Gate (Yalı Köşkü Kapısı).

From there, the wall turned inland toward the Strategion, which was the city’s military parade ground—similar to the Champ de Mars in Paris. This area stretched across the plain at the foot of the Second Hill, between the Yali Kiosk Gate and the modern-day Sirkeci Train Station.

The Baths of Achilles and Brass Market

Near the Strategion stood the Thermae of Achilles, or the Baths of Achilles, a public bathhouse popular in the ancient city. A city gate once stood there as well and was later known as the Arch of Urbicius.

From that point, the wall climbed the slope up to the Chalcoprateia, or Brass Market, which was one of Byzantium’s major trading centers. This market extended from the area now occupied by the Sublime Porte (the Ottoman imperial gate) to the region of Yerebatan Sarayı—today’s Basilica Cistern, one of the most visited sites in modern Istanbul.