It was the mystery and romance of some of the wonderful pictures of a nineteenth-century explorer that first led me into the relatively unknown region between the Apurimac and the Urubamba, sometimes called "the Cradle of the Incas."

In that volume is a marvelous picture of the Apurimac Valley.

The desire to see the Apurimac and experience the thrill of crossing that bridge decided me in favor of an overland journey to Lima.

As readers of "Across South America" will remember, these ruins were at Choqquequirau, an interesting place on top of a jungle-covered ridge several thousand feet above the roaring rapids of the great Apurimac.

The prefect insisted that the ruins represented the residence of the Inca Manco and his sons, who had sought refuge from Pizarro and the Spanish conquerors of Peru in the Andes between the Apurimac and Urubamba rivers.

It was relatively easy for him, with a handful of followers, to dash out of the mountain fastnesses, cross the Apurimac River either by swimming or on primitive rafts, and reach the great road between Cuzco and Lima, the principal highway of Peru.

They were sent back by one of the western routes across the Apurimac.

One company was sent by way of Limatambo to Curahuasi, to head off the Inca in case he should cross the Apurimac and try to escape by one of the routes which had formerly been used by his father, Manco, in his marauding expeditions.

Yet before our visit nearly all the Peruvian historians and geographers except Don Carlos Romero still believed that when the Inca Manco fled from Pizarro he took up his residence at Choqquequirau in the Apurimac Valley.

The Mapillo flows into the Apurimac near the mouth of the river Pampas.

He must have had rafts or canoes on which to cross the Apurimac, which is here very wide and deep.

In the valleys between Huarancalque and Lucma, Manco was cut off from central Peru by the Apurimac and its magnificent canyon, which in many places has a depth of over two miles.

This ignorance led the Peruvian geographers Raimondi and Paz Soldan to conclude that Choqquequirau, the only ruins reported between the Apurimac and the Urubamba, must have been the capital of the Incas who took refuge there.

The Indians said that Conservidayoc lay in a westerly direction from Vilcabamba, yet on Raimondi's map all of the rivers which rise in the mountains west of the town are short affluents of the Apurimac and flow southwest.

Raimondi, followed by the Royal Geographical Society, did not leave room enough for such a range to exist between the rivers Apurimac and Urubamba.

Yet according to the latest map of this region, published in the preceding year, this was the very position of the river Apurimac itself, near its junction with the river Pampas.

The mystery was finally solved by Mr. Bumstead in 1912, when he determined the Apurimac and the Urubamba to be thirty miles farther apart than any one had supposed.

We supposed from our maps that we were now looking down into the basin of the Apurimac.

Instead of being the Apurimac Basin, what we saw was another unexplored region which drained into the Urubamba!

Harry B. Ferris, M.D.: The Indians of Cuzco and the Apurimac.

Osgood Hardy: Cuzco and Apurimac.