 The exact route taken by Odaenathus from Palmyra to Ctesiphon remains uncertain ; it is probably similar to the route emperor Julian took in <unk> during his campaign against Persia . Using this route , Odaenathus would have crossed the Euphrates at <unk> then moved east to Edessa followed by Carrhae then Nisibis ; here , he would have descended south along the <unk> River to the Euphrates valley and marched alongside the river 's left bank to Nehardea . After taking the city , he penetrated the Sassanian province of <unk> and marched along the royal canal <unk> towards the <unk> where the Persian capital stood . 
