Assassin Den

"You know the Borgia Towers? You don't have that but you have something that's an evolution of that, you have something that's an evolution of city improvement, and all of that's consolidated in the Assassin's Dens."

- Official Xbox Magazine.

Assassin Dens were reclaimed Templar Towers, which could be found around the city of Constantinople during the Renaissance. They functioned similarly to the Borgia Towers of Rome.

History
During 1511, Ezio Auditore liberated the structures from the Byzantine Templars' control, using several strategic attacks; he then replaced the Templar influence with well-ordered den of his fellow Assassins. However, whenever his notoriety rose, Templars would attempt to retake the dens. Ezio would either lead a direct assault to reclaim it or send Apprentices to take care of it for him.

Ezio would also select Master Assassins to guard the Dens for him so that the Templars could not retake them, regardless of his notoriety.

Trivia

 * Retaking a den will increase the amount of ziplines in the district.
 * It has been stated by Alexandre Amancio that Assassin Dens will play an integral part in the development and creation of Ezio's Bombs.