 "Encyclopædia Iranica" suggests a number of defenders of just 700 (or no more than 2,000) men based on the maximum number of troops likely at Ariobarzanes' disposal, but it notes that most modern historians follow Arrian, Curtius, and Diodorus unreservedly.The Persian Gate was only a couple of meters wide at the point of ambush.Once the Macedonian army had advanced sufficiently into the narrow pass, the Persians rained down boulders on them from the northern slopes.