Immediately after leaving Kherrata the road plunges suddenly into the mouth of the gorge, which is about four miles in length. The valley contracts until it becomes so narrow that one can toss a stone across it; the river, pent in between its walls of rock, rushes like a mill-race; the road alternately creeps along a narrow shelf cut in the face of the overhanging cliff, is borne by lofty arches above the rushing torrent, or by means of tunnels pierces the obstructing masses of rock. In places the precipice drops a thousand feet sheer to the river; at others one looks up between the narrow walls to peaks which tower nearly a mile and a half into the blue. Tributary streams come roaring down through leafy glens to hurl themselves over the edge of the abyss into the river below amid a smother of spray and spume. Yawning in the mountain-side are mouths of black, mysterious caverns. Troops of Barbary apes leap from crag to crag, or, looking down like gargoyles from the heights, chatter excitedly at the passer-by. Even this road has echoed to the tramp of the legions. Mr. Hilaire Belloc tells of a French general who, during the campaign against the Kabyles, succeeded in leading his column through the defile, which up to that time had been considered impassable even for an Arab on foot. Justifiably proud of the achievement, he sent a detail to inscribe a record of it on the face of the cliff. A few hours later the men returned to report that there appeared to be lettering on the cliff already. Upon examination the time-worn inscription read, “Legio III Augusta.”