The modern world edges into one of the cradles of humankind

AT THE END of a long day, we walked up to the village of Korcho. Tropical boubou birds were singing their duets on the edge of a lake. Circular huts, made of sticks and crowned with grass roofs, lay scattered along a ridge. Boys were herding cattle toward the family stockades for the night.

Korcho is a village of the Kara people, one of the 16 ethnic groups said to inhabit Ethiopia’s Omo-Turkana Basin. Ethiopia may be known for its rich and varied mix of ethnicities, but the diversity in the lower Omo River Valley in the southwest of the country, home to more than 200,000 people, is unparalleled.

One of the cradles of humankind, the valley was declared a World Heritage site by UNESCO in 1980. Ancient stone tools unearthed there “offer evidence of the earliest known technical activities of prehistoric beings,” the UNESCO citation reads. The discovery of several hominid fossils has provided vital keys to an understanding of human evolution.

Such has been the isolation of these peoples that until fairly recently few had even heard of the nation of which they were a part. For them, the capital of Addis Ababa might have been another world. To outsiders, the valley appears little compromised by the trappings of modernity.

But inevitably the modern world has edged in. The Ethiopian government is creating a cascade of five dams on the upper Omo, a mighty river that winds for 500 miles through the central highlands and empties on the border with Kenya into Lake Turkana, the world’s largest desert lake.

The Gibe III dam in particular, opened in 2015, has already had a profound effect on the hydrology of the lower Omo, disrupting the annual floods that support cultivation and pasturage and undermining a way of life that has flourished here for many centuries. Power lines now stretch across green hillsides flanking the dam reservoir. Some communities are being resettled.

I had come to the Omo from Addis Ababa, driving for three days across the agrarian landscapes of the Ethiopian highlands on roads where most of the traffic was pedestrian. Young men strolled arm in arm while women staggered in their wake beneath heavy sacks. A few horsemen passed. A white-robed priest appeared beneath a splendid parasol.

Ethiopia strains the imagination. The presence of what is believed to be the Ark of the Covenant, housed in an unassuming chapel in the northern town of Aksum, offers a hint of what this world of cloud-high plateaus and plunging gorges, of peaks and blistering salt deserts, of monasteries and castles, would reveal to me.

To ancient Egyptians, Ethiopia was the Land of Punt, a mysterious world where the Nile River flowed from fountains. Medieval Europeans believed it was a place inhabited by unicorns and flying dragons, birthplace of Prester John, keeper of the Fountain of Youth, protector of the Holy Grail, and a supposed descendant of one of the three magi.