Lacoeur's villa

Lacouer's villa was a villa located north of the city gardens of Jerusalem at the time of the Third Crusade.

History
In 1190, while the Crusaders held the city, the King of Jerusalem hosted a grand party at this villa, inviting members of the local nobility. The Assassin Altaïr Ibn-La'Ahad, in search of the Templar Grand Master Basilisk, who held a key to the Temple of the Sand, thought this party gave him an opportunity to strike without dealing with the heavy defenses of the king's palace. Unbeknownst to him, this villa itself had substantial fortifications, such that the Assassin concluded that a stealthy infiltration was impossible. As a result, he launched a solo assault of the villa through the front entrance, sending the entire complex on high alert. Despite being outnumbered, he managed to rout the defenses of the outer sections, prompting the alarmed guards to raise the drawbridge to the inner courtyards in the hopes of denying any further advance. This failed spectacularly as Altaïr scaled past the walls with his grappling hook.

Even so, Altaïr would have faced difficulty penetrating the castle that comprised the core of the villa, if not for a spy that informed him of a secret passageway under a moat. After draining the water from this moat, the Assassin infiltrated the keep through the sewers. He exited through a hidden doorway in the form of a rotating stone wall and chanced upon an isolated Basilisk. Their duel lasted briefly, as Altaïr's only intention was to steal the key wrapped around the Grand Master's neck. Once he secured this item, he promptly aborted the fight, fleeing to the frustration of Basilisk, who had relished a challenging battle.

Reference

 * Assassin's Creed: Altaïr's Chronicles