In consequence of this decision, orders were sent to Diognetus the commander of the fleet to sail towards Seleucia: while Antiochus himself started from Apameia with his army, and encamped near the Hippodrome, about five stades from the town. He also despatched Theodotus Hemiolius with an adequate force against Coele-Syria, with orders to occupy the passes and to keep the road open for him. The situation of Seleucia and the natural features of the surrounding country are of this kind. The city stands on the sea coast between Cilicia and Phoenicia; and has close to it a very great mountain called Coryphaeus, which on the west is washed by the last waves of the sea which lies between Cyprus and Phoenicia; while its eastern slopes overlook the territories of Antioch and Seleucia. It is on the southern skirt of this mountain that the town of Seleucia lies, separated from it by a deep and difficult ravine. The town extends down to the sea in a straggling line broken by irregularities of the soil, and is surrounded on most parts by cliffs and precipitous rocks. On the side facing the sea, where the ground is level, stand the market-places, and the lower town strongly walled. Similarly the whole of the main town has been fortified by walls of a costly construction, and splendidly decorated with temples and other elaborate buildings. There is only one approach to it on the seaward side, which is an artificial ascent cut in the form of a stair, interrupted by frequently occurring drops and awkward places. Not far from the town is the mouth of the river Orontes, which rises in the district of Libanus and Anti-Libanus, and after traversing the plain of Amyca reaches Antioch; through which it flows, and carrying off by the force of its current all the sewage of that town, finally discharges itself into this sea not far from Seleucia.