“The mountain on the opposite or left bank of the river,” says Colonel Leake, whose topography of the Grecian battles founded on minute personal inspection, is no less valuable than interesting, “is the northern extremity of the great ridge of Nemertzika, Asnaus, much lower than that summit, but nearly equal to Trebusin in height. At the top, it is a bare, perpendicular precipice, but the steep lower slope, unlike that of its opposite neighbor, is clothed with trees quite to the river. Through the opening between them is seen a magnificent variety of naked precipices and hanging woods, inclosing the broad and rapid stream of the insinuating river.”[10] The road,[11] difficult in any event to an army, if defended, is impracticable. In this prodigiously strong pass Philip had taken post, occupying the narrow road with the phalanx, and having his main body hutted comfortably among the loose crags of Aëropus, on a conspicuous summit of which was pitched his own royal pavilion, with the banner of Alexander waving over it. The slopes of the opposite hill, Asnaus, was held by Athenagoras his lieutenant, with the light troops, and all the flanking crags and salient angles of the precipitous hills were mounted with the tremendous military engines, which, though of common use in the defense and attack of fortresses, had never been brought into field service until now. Immediately in front of this stern mountain gateway extended a small plain, midway between the Roman camp and the Macedonian lines, and here, after a fruitless parley and attempt at accommodation, from which both parties retired so much exasperated at their mutual pertinacity, that the river, which divided them, alone prevented their personal conflict, the light troops met in action from both armies. It is scarce to be conceived how, with such obstacles against them, the Romans could have escaped destruction; but it is almost ever the case in mountain warfare that the attacking party is successful. The gray mists of the early summer morning were still nestling among the crags, and brooding in the deep glades of the hanging woods, when the long, shrill blasts of the Roman trumpets announced the impetuous rush of the light troops; and on they went, headlong and invincible, carrying all before them, and driving in the Macedonian skirmishers like the foam of the Adriatic before the fury of the south-east wind.