In 1453, which important city fell?

The story behind the answer

Constantinople fell in 1453 to the Ottoman Turks under Sultan Mehmed II after a 53-day siege, ending the thousand-year Byzantine Empire. Giant cannons shattered the famed Theodosian Walls, signaling a shift to gunpowder warfare. Control of this strategic city on the Bosporus reshaped trade and power in the eastern Mediterranean; Hagia