The army marched in three grand divisions. One entered Bavaria, joined to itself recruits raised in that country, and descended the Danube in boats, which carried also an abundance of provisions and military stores. A second division, under Charlemagne himself, marched along the southern side of the river; and a third, under his generals Theoderic and Meginfried, along its northern banks. The emperor had besides sent orders to his son Pepin, king of Italy, bidding him to lead an army of Lombards and other Italians to the frontier of Hungary, and co-operate with the other troops. Before telling the story of the expedition, it behooves us to give some account of the country which the king of the Franks was about to invade, and particularly to describe the extraordinary defences and interior conditions with which it is credited by the gossipy old Monk of St. Gall, the most entertaining, though hardly the most credible, writer of that period. All authors admit that the country of the Avars was defended by an ingenious and singular system of fortifications. The account we propose to give, the Monk of St. Gall declares that he wrote down from the words of an eye-witness, Adelbart by name, who took part in the expedition. But one cannot help thinking that either this eye-witness mingled a strong infusion of imagination with his vision, or that the monk added fiction to his facts, with the laudable purpose of making an attractive story. Such as it is, we give it, without further comment. Nine concentric circles of palisaded walls, says the garrulous old monk, surrounded the country of the Avars, the outer one enclosing the entire realm of Hungary, the inner ones growing successively smaller, the innermost being the central fortification within which dwelt the Chagan, with his palace and his treasures. These walls were made of double rows of palisades of oak, beech, and pine logs, twenty feet high and twenty feet asunder, the interval between them being filled with stone and lime. Thus was formed a great wall, which at a distance must have presented a singular appearance, since the top was covered with soil and planted with bushes and trees. The outermost wall surrounded the whole country. Within it, at a distance of twenty Teutonic, or forty Italian, miles, was a second, of smaller diameter, but constructed in the same manner. At an equal distance inward was a third, and thus they continued inward, fortress after fortress, to the number of nine, the outer one rivalling the Chinese wall in extent, the inner one--the _ring_, as it was called--being of small diameter, and enclosing a central space within which the Avars guarded the accumulated wealth of centuries of conquest and plunder.