The victory of Charles Martel, in 733, had set a bound to the Saracens' invasion of Europe; they no longer thought of further conquest, but turned to the work of consolidating the kingdom they had acquired. After the brief and disastrous incursion of Charlemagne, they were left in almost undisturbed possession of their new territory for a period of three hundred years. It is true the descendants of the expelled Goths still held out in stubborn independence in the mountainous districts of the north, and from time to time recovered a portion of their ancient dominion; but these inroads, while they gave some trouble, did not materially endanger the domination of the Moors over the greater part of Spain until the eleventh century. The conquerors accepted the independence of the northern provinces as an inevitable evil, which would cost more blood to remove than the feat was worth; and leaving Galicia, Leon, Castile, and the Biscayan provinces to the Christians, they contented themselves with the better part of the land: the Christians might enjoy the dreary wastes and rocky defiles of the north, provided they did not interfere with the Moors' enjoyment of the warm and fertile provinces of the south and east. From the end of the eighth century, when the Moorish boundaries took a tolerably final shape, to the time of the advance of the Christian kingdoms in the eleventh century, the division between the Christian north and the Moslem south may be roughly placed at the great range of mountains called the Sierra de Guadarrama, which runs in a north-easterly direction from Coimbra in Portugal to Zaragoza, from whence the Ebro may be taken as a rough boundary. The Moors thus enjoyed the fertile valleys of the Tagus, the Guadiana, and the Guadalquivir--the very name of which bears witness to its Arab owners, for Guadalquivir is a corruption of the Arabic Wady-l-kebīr, or the "Great River"--besides possessing the famous cities of Andalusia, the wealth and commerce and climatic advantages of which had been celebrated from Roman times. The division was a natural one; the two parts have been distinguished geographically from time immemorial, on account of their climatic differences. The north is bleak and exposed to biting winds, subject to heavy rains and intense cold; a good pasturage country, but in most parts ill to cultivate. The south, while tormented by the hot winds that blow over from Africa, is genial, well watered, and capable of high cultivation. A great plateau divides the two, and though this fell chiefly on the Moorish side, it was to some extent debatable land and insecurely held. Its chilly heights rendered it distasteful to lovers of sunshine like the Moors, and they confided it chiefly to the care of the Berber tribes who had first come over with Tārik, and who were always held in poor estimation by the true Arabs who reaped the fruits of the conquest. [Illustration: ALCANTARA.]