three principal centres of population and culture,—the coast, the sierra, and the Titicaca plateau. These centres did not arrive at the height of their power contemporaneously, nor were they necessarily related to one another, though the influence of each one is seen, in some degree, in the development of all three. A distinct, and undoubtedly a very ancient, architecture prevails in the temples, palaces, and pyramids of the coast, unidentified either with that of the interior valleys or of the high plateau. The magnificent ruins of Chimu culture, as seen in the great walls of Chan-Chan, which measure from twenty to thirty feet in height, and show wonderful designs and stucco work on their surface, as well as the monuments of an earlier people, as seen at Huaca del Sol, near Moche, and the temple Pachacámac, are of a different character from the edifices of Huánuco Viejo in the sierra, of Sacsahuaman at Cuzco, and of the pillars and round tower (Pelasgian style) in Puno; while these latter ruins bear little relation in construction to the cyclopean edifices of Tiahuanaco, in Bolivia, the centre of what is sometimes called the Aymará culture. [Illustration: CARVED TERRACES OF THE PALACE OF CHAN-CHAN.] [Illustration: ANIMAL CARVINGS ON THE WALLS OF CHAN-CHAN.] Aside from their scientific importance, the antiquities of Peru are interesting to travellers because they have many features that appeal to one’s imagination and love of mystery. They lie out of the beaten track of the sightseer, who journeys annually, guide-book in hand, to gaze on the ruins of their Egyptian and Pelasgian contemporaries in the Old World. But they possess the greater fascination of the unsolved problem, made doubly attractive by apparently innumerable “clues,” which stimulate the imagination and tempt one to construct independent theories as to their origin and antiquity. Karnak and the Pyramids may be no more ancient than Nasca; certainly the Sphinx is not nearly so great an enigma as are the _huacas_ of Trujillo and Ancón cemeteries; and there is nothing in Oriental antiquities that quite resembles the mummies taken out of one of these mysterious burial mounds. [Illustration: RUINS OF CHAN-CHAN.]