At its peak there was a garrison of 2000 soldiers here and stabling for hundreds of horses.
I stood in the gloom of the arched stables and listened to the water still dripping into the adjacent cavernous cisterns - water was the lifeblood of castles like these.
It had been raining heavily so the encircling moat between the outer walls and inner fortress was partly full of water.
No wonder the castle was never breached - attackers would have been under constant fire just to reach the moat and if they made it that far the water they'd have to negotiate would have been full of the contents of the castle's latrines (which I thought still smelled a bit whiffy, but maybe that was my overactive imagination).
For those living in the inner keep, life was a little more refined. The great hall and chapel were adorned with carvings, vaulted ceilings and arched windows. A huge bread oven probably helped ward off some of the winter chill.
Krak des Chevaliers is magnificent but for sheer audaciousness nothing can beat the siting of the Qala'at Salah ad-Din - known to the Crusaders and to Lawrence of Arabia as Saone in recognition of its founder Robert of Saone.
The 12th century castle is built on a knife-edge ridge - protection enough from attackers one would have thought. But to make it even more impregnable the Crusaders hacked through the solid rock to create a fortified island. They left a soaring spire of rock on which a drawbridge could be perched.
"I grew up here," said my guide, as we peered down from the five-metre-thick postern gate walls into the ravine.
He thinks he was probably the first baby to be born in the fortress since Saladin captured it. When restoration work began in the 20th century his father had been its first caretaker and the family lived on site.
He had taken over his father's role and as custodian obviously considered it appropriate to light a brazier in the Gate Tower and then brew some tea.
The wood crackled, firelight burnished the stone walls and smoke drifted through the lofty arched doorway into the inner courtyard. If a knight on horseback had appeared at the entrance I wouldn't have been at all surprised.