The Santa has the distinction of being the largest river in Peru flowing into the Pacific Ocean. Rising among the heavily snow covered peaks of the White Cordillera, though nowhere navigable it has a large water supply for irrigation, made use of by the Incas. It could easily be made available for a large district back of Chimbote. At present the railway serves only a few sugar plantations on the lower part of the river’s course, but its further construction will open up immense coal fields, and farther on in the Huailas Valley great mineral deposits of gold, silver, etc., and a fine though limited agricultural district which already has a large population. The Huailas Valley has on the east the Cordillera Blanca, whose splendid snow capped summits rise to an altitude of 20,000 to 22,000 feet; on the west the Cordillera Negra reaches a height of 17,000 to 18,000 feet; the passes into the valley are above 14,000. The floor of the valley rises from 3000 feet at the north to 10,000 at Huarás and 11,000 at Recuay. Along the way are the considerable towns of Caráz, Yungay, Carhuaz, and Huaráz, capital of the Department, each with populations of from 5000 to 10,000, besides the people at _haciendas_ and at mining centers on either hand. This has been called the richest and most thickly settled portion of Peru. All sub-tropical and temperate productions flourish here at various elevations; the mineral riches may rival the Klondike as the scenic splendor surpasses that of Chamonix. East of Yungay rises the magnificent twin-peaked Huascarán, the first and only ascent of which was made by the author with two Swiss guides, September 2, 1908; the north peak, altitude 21,812 feet, is still, 1921, the highest point in all America yet attained by any North or South American.