Masyaf is the Assassin Brotherhood headquarters in the first Assassin's Creed game. It is presented as a fortified mountain settlement in Syria and serves as Altaïr Ibn-La'Ahad's home base during the Third Crusade.
The settlement is controlled by Al Mualim, the leader who commands the Levantine Assassins. Altaïr returns to Masyaf after missions to receive information, report his progress, and obtain new assignments. The location therefore functions as both a narrative hub and a symbol of the Brotherhood's organization.
Masyaf is based on a real town in western Syria. The historic settlement is associated with the Nizari Ismaili state and a medieval fortress, although the game's Assassin lore is heavily fictionalized and should not be treated as a literal history of the site.
Masyaf also appears in later Assassin's Creed material, especially Assassin's Creed: Revelations. It should not be confused with Monteriggioni, which serves as Ezio's Italian base in Assassin's Creed II.