The Hospitallers (the Knights of St. John) completed the mighty castle in 1173. In the summer of 1187, the Crusader armies were crushed by the Arabs under Saladin at the Horns of Hittin, west of Tiberias, bringing an end to the Latin Kingdom of Jerusalem with one decisive battle. Their remnants struggled on to Tyre (in modern Lebanon), but Belvoir alone refused to yield; 18 months of siege got the Muslims no farther than undermining the outer eastern rampart. The Crusaders, for their part, sallied out from time to time to battle the enemy, but their lone resistance had become pointless. They struck a deal with Saladin and surrendered the stronghold in exchange for free passage, flags flying, to Tyre.
Don't follow the arrows from the parking lot; instead, take the wide gravel path to the right of the fortress. This brings you to the panoramic view and the best spot from which to appreciate the strength of the stronghold, with its deep, dry moat, massive rock and cut-stone ramparts,
and gates. Once inside the main courtyard, you're unexpectedly faced with a fortress within a fortress, a scaled-down replica of the outer defenses. Not much remains of the upper stories; in 1220, the Muslims systematically dismantled Belvoir, fearing another crusade. Once you've explored the modest buildings, exit over the western bridge (once a drawbridge) and spy on the postern gates, the protected and sometimes secret back doors of medieval castles.