At a short distance from the Saltus Castulonensis, one of the northernmost points of the Sierra Morena, in the Province of Jaen (Spain), the mountains become blended, to the east, with a seines of ranges running with a southerly trend towards the Sierra Nevada. This, in its turn, is merged into other ranges that stretch their arms to the coast of the Mediterranean on the south; while their main body continues to the west towards the mouth of the River Baetis, and terminates in a series of elevations, which include those known to the Romans as the Ilipula Mountains, the Alpujarras of modern times. From, my point of departure, and to turn again to the north, the Sierra Morena, which the Romans knew as the Montes Mariani, stretches away in a south-westerly direction, broken here and there by valleys and gorges, but still forming a continuous range, until it dips into the sea on the eastern side of the River Anas, the Guadiana of modern geography. These mountain ranges, or rather groups of ranges, form the eastern and western watersheds of the River Baetis. Indeed, they may be said to form the casket which encloses the jewel of the Spanish peninsula, the rich, the fertile, the beautiful Baetica of the Romans, the Andalucia of to-day.