To travel to Ethiopia’s remote Omo River Valley is to wade into a morass of moral ambiguities. You will be on a safari where people—not wildlife—are the attraction. You will observe ...

Spanish photographer Diego Arroyo took a trip to Ethiopia's Omo River Valley to find the world's most ancient tribes.

Art ventures into the Omo Valley, Ethiopia’s nearly inaccessible and richest tribal zone.

When I visited the Omo Valley in southern Ethiopia almost two decades ago, there were few dirt roads, and tribes lived in mud huts and were mostly naked except for spectacular body paint.

Over the past few years, traditional tribal life in the Omo Valley, Ethiopia, is claimed to have been threatened by modern developments.

Occasionally they are deployed in skirmishes between the different tribes of the Omo Valley, Biwa says, or used to kill the huge crocodiles that thrash in the river’s chocolatey brown waters.

Over the past few years, traditional tribal life in the Omo Valley, Ethiopia, is claimed to have been threatened by modern developments.