In Assassin's Creed Revelations, which historic city is Ezio's main base?

In Assassin's Creed Revelations, Constantinople is Ezio's main base.

Ezio travels to Constantinople, the capital of the Byzantine Empire, while searching for keys connected to Altaïr's legacy. The city is presented as a major crossroads where Byzantine, Ottoman, and international communities meet. Its districts include Constantinople and the nearby suburb of Galata.

The story takes place in the early sixteenth century, when Sultan Bayezid II rules the Ottoman Empire. Ezio becomes involved in a succession dispute and works with Yusuf Tazim, leader of the local Assassin Brotherhood. The city also provides the setting for Ezio's encounters with Prince Suleiman.

Constantinople is the historical name used for the city now known as Istanbul. Damascus is linked to the first game, while Alexandria is central to Origins and Athens to Odyssey.