Masyaf is the Assassins’ headquarters in the first Assassin’s Creed game, set in 1191.
The mountain settlement is home to the Assassin leader Al Mualim and serves as Altaïr Ibn-La'Ahad’s base. Altaïr returns there for guidance, equipment, and story developments between missions in the Levant.
The game also takes Altaïr to Jerusalem, Acre, and Damascus. Those cities are important investigation and assassination locations, but they are not the Brotherhood’s headquarters. This distinction is a common source of confusion because Masyaf is visited less frequently than the major target cities.
Historically, Masyaf was a real Syrian fortress associated with the Nizari Ismailis, a community often linked in popular culture with the medieval Assassins. The game combines that historical setting with fictional characters and events.