As the story of the necromantic tower is one of the most famous as well as least credible points in the history of Don Roderick, it may be well to fortify or buttress it by some account of another marvel of the city of Toledo. This ancient city, which dates its existence almost from the time of the flood, claiming as its founder Tubal, the son of Japhet, and grandson of Noah,[28] has been the warrior hold of many generations and a strange diversity of races. It bears traces of the artifices and devices of its various occupants, and is full of mysteries and subjects for antiquarian conjecture and perplexity. It is built upon a high rocky promontory, with the Tagus brawling round its base, and is overlooked by cragged and precipitous hills. These hills abound with clefts and caverns; and the promontory itself, on which the city is built, bears traces of vaults and subterraneous habitations, which are occasionally discovered under the ruins of ancient houses, or beneath the churches and convents. [28] Salazar, _Hist. Gran. Cardinal. Prologo_, vol. i. plan 1. These are supposed by some to have been the habitations or retreats of the primitive inhabitants; for it was the custom of the ancients, according to Pliny, to make caves in high and rocky places, and live in them through fear of floods; and such a precaution, says the worthy Don Pedro de Roxas, in his history of Toledo, was natural enough among the first Toledans, seeing that they founded their city shortly after the deluge, while the memory of it was still fresh in their minds. Some have supposed these secret caves and vaults to have been places of concealment of the inhabitants and their treasure during times of war and violence; or rude temples for the performance of religious ceremonies in times of persecution. There are not wanting other, and grave writers, who give them a still darker purpose. In these caves, say they, were taught the diabolical mysteries of magic; and here were performed those infernal ceremonies and incantations horrible in the eyes of God and man. “History,” says the worthy Don Pedro de Roxas, “is full of accounts that the magi taught and performed their magic and their superstitious rites in profound caves and secret places; because as this art of the devil was prohibited from the very origin of Christianity, they always sought for hidden places in which to practice it.” In the time of the Moors this art, we are told, was publicly taught at their universities, the same as astronomy, philosophy, and mathematics, and at no place was it cultivated with more success than at Toledo. Hence this city has ever been darkly renowned for mystic science; insomuch that the magic art was called by the French, and by other nations, the Arte Toledana.