Masyaf castle, Syria.

Masyaf Castle is located in the town of Masyaf in Hama Governorate, Syria, situated in the Orontes Valley, approximately 40 kilometers to the west of Hama. It served to protect the trade routes to cities further inland such as Banyas. The citadel became famous as the stronghold from which Rashid ad-Din Sinan, known as the Old Man of the Mountain ruled. He was a leader of the Syrian wing of the Hashshashin sect, also known as the Assassins, and a figure in the history of the Crusades.