▁the ▁Muslim ▁holy ▁cities ▁of ▁Me cca ▁and ▁Med ina ▁in ▁the ▁He j az . ▁Trib es men ▁also ▁served ▁as ▁desert ▁gu ides ▁for ▁the ▁army ▁and ▁state ▁officials . ▁The ▁am ir ▁al - ʿ arab ▁was ▁further ▁responsible ▁for ▁collect ing ▁zak at ▁( du es ) ▁on ▁the ▁liv est ock ▁of ▁the ▁Bed ou in ▁tribes . ▁ ▁During ▁Sultan ▁Bay bar ' s ▁reign ▁( 1 2 6 0 – 1 2 7 7 ), ▁a ▁bar id ▁( post al ▁route ) ▁was ▁created ▁between ▁Egypt ▁and ▁Sy ria , ▁which ▁enabled ▁the ▁s ultan ▁to ▁remain ▁constantly ▁not ified ▁of ▁develop ments ▁in ▁the ▁provinces . ▁It ▁served ▁as ▁a ▁major ▁central izing ▁factor ▁in ▁the ▁M aml uk ▁state , ▁and ▁each ▁postal ▁station ▁required ▁transport ▁horses , ▁which ▁the ▁tribes ▁provided . ▁According ▁to ▁S ato , ▁the ▁tribes ' ▁supply ▁of ▁horses ▁and ▁cam els ▁was ▁" ind isp ens able ▁for ▁the ▁maintenance " ▁of ▁the ▁bar id . ▁No ble ▁horses ▁and ▁young ▁cam els ▁were ▁also ▁provided ▁by ▁the ▁am ir ▁al - ʿ arab ▁to ▁the ▁royal ▁st ables ▁of ▁the ▁M aml uk ▁s ult ans ▁on ▁an ▁annual ▁basis . ▁Under ▁the ▁early ▁Ott om ans , ▁the ▁am ir ▁al - ʿ arab ▁was ▁required ▁to ▁provision ▁the ▁s ultan ' s ▁st ables ▁with ▁ 1 , 0 5 0 ▁young ▁cam els ▁and ▁ 3 0 ▁young ▁horses , ▁the ▁collect ive