Carhuasanta

Carhuasanta is a small river located in the Arequipa Region of Peru. It is known as the headwaters of the Amazon River. The brook is fed by the winter snows of Nevado Mismi, (5,597 m), some 6,400 kilometers from the Atlantic Ocean. Of all the possible river sources in the Amazon Basin, it is the snow melt of the Carhuasanta that has been calculated by cartographers to be the furthermost water source from the mouth of the Amazon.

The Carhuasanta joins with the Quebrada Apacheta, becoming the Rio Lloqueta. The river has several more name changes before it becomes the Apurímac River. The mining town of Caylloma lies near the junction of four rivers that form the Apurímac river.

The National Geographic Society sent a three-man expedition to the region in 1971, headed by Loren McIntyre. The expedition travelled from Caylloma by four-wheel drive, but soon got bogged. Continuing on by backpacking up the river, they climbed up the Apacheta Trail and traversed onto the mountain Mismi, taking in the mountains Kiwicha and Pumachiri. This is, as McIntyre describes it in his 1972 National Geographic article, "a semicircle rampart of the continental divide. All that trickles from the inner rim joins to form the Apurimac."

On 15 October 1971, we reached an ice-edged ridge above Carhuasanta, longest of the five headwater brooks. The Indians call that 18,200 foot summit Choquecorao ... A thousand feet below the ridge we sighted a lake... We clambered down to quench our thirsts... Here at 17,220 ft/5,249m was the farthest source of the mighty Amazon - more a pond than a lake, just a hundred feet across.

Mismi makes an unreliable source of water in the dry season. Laguna McIntyre, as the lake was called, is deemed the 'true source', as it is permanent. However, it is known that the source will change over time, perhaps in a single season, due to the changes of the weather and its impact on the microclimate. In the wet season the mountains and undulating altiplano are covered in snow. In the dry season it resembles a desert as the mountains crumble slowly to dust. The effect of global warming will no doubt accelerate the changing of the Amazon's source water.

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Wikipedia