Constantinople is the city Ezio Auditore explores in Assassin's Creed Revelations while searching for Altaïr's legacy.
The game sends the older Ezio to Constantinople, the capital of the Byzantine Empire, in the early sixteenth century. He seeks keys connected to Masyaf and Altaïr's memories, while also becoming involved with the local Assassin Brotherhood and the political struggle between Byzantine and Ottoman forces.
Constantinople is the historical name used for the city during the game's period; it was later widely known as Istanbul. The game also includes Cappadocia as a separate region, but Constantinople is the principal urban setting and the center of Ezio's activities.
Revelations links three major parts of the series' mythology. Ezio is the active protagonist, Altaïr appears through memories, and Desmond Miles remains connected through the Animus in the modern-day storyline. This makes the game a direct bridge between Ezio's Renaissance adventures and Altaïr's medieval story.