1. The byzantine tower of Galata (in greek – Megalos Pyrgos)
The suburb of Sykai (named also Galata and Pera) on the north shore of the Golden Horn was fortified in the 6th c. A massive iron chain stretched across the gulf under the water was connected to the nearest point on the southern shore, to regulate entering and exiting ships. A little part of the chain, just large enough for the ships to pass through, was opened when the toll was paid, allowing merchant ships to sail through the harbor. From the early fortification after the 7th c., only the Tower of Galata survived; it guarded the chain, extending across the mouth of the Golden Horn. The Tower would serve as the customs station for incoming merchant ships.
The most important episode linked with the Great Tower of Galata happened during the siege of Constantinople by the knights of the Fourth Crusade. Military operations were reported in detail by the French knights Robert of Clary and Geoffroi Villehardouin.1 After the 5th of July 1203 the French knights, guided by Baldwin of Flanders, sieged the Tower but did not seize it. According to the report of Robert de Clary, assumption have been made that the Tower was aproximately 100 feet high, like most of the other city towers.
It is supposed that the tower existed during the Latin Empire of Constantinople. After the sack of Constantinople in 1204, Galata was in the Venetian part of the city, and after the restoration of the Byzantine rule, the quarter became a Genoese colony, outside of Byzantine control.2 Nowadays, nothing is visible from the byzantine edifice.
2. The Genoese Tower in Galata (Christea Turris - Tower of Christ; Turkish - Galata Kulesi)
The Genoese founded their colony in Galata after 1273 and maintained dominance in the region untill 1682. The Genose were bound by a strict rule that didn't allow them to erect towers or fortresses. But despite the negative reaction of the Byzantine government, the Genoese managed to protect their quarter with a moat and also with walls that joined their castle-like houses. The first enclosure they built to surround their colony was named Magnifica communita di Pera. With the emperor’s of 1302, the Genoese in Galata/Pera were allowed to erect these fortress walls.3 The tower, then called Christea Turris was built in 1348 at the northernmost and highest point of the quarter. It is aproximately 66.90 meters tall - having been the city's tallest structure when built. The elevation at ground level is 35 meters above sea-level, the external diameter is 16.45 m., the internal diameter is 8.95 m., and the walls are 3.75 m. thick.
After the Ottoman conquest, the tower was rebuilt several times serving as a watch tower for fires. It was used as an observatory during the 17th c. Many legends and stories are linked with the edifice, among which the story of Hezarfen Ahmed Çelebi, who used artificial wings to fly from the top of the tower to Bosphorus in 1638.4
Today the tower is in the neighbourhood of Beyoglu, and is a visible landmark thoughout the city of Istanbul.