Researchers studied an old wall at Oued Beht in northwestern Morocco. They dug at the site in 2023. The wall is about 4,000 to 3,500 years old. It probably helped protect people and their land.
The wall stands on a narrow part of a hill above a river. People also dug a cut in the ground as part of the building work. This is the oldest known large structure for protection in North Africa outside the Nile Valley. Building it needed planning and many people working together.
Researchers do not know exactly why people built it. They may have competed for land and other things they needed, or tried to control travel through the area. These communities also had links with other places around the Mediterranean Sea. Earlier people at Oued Beht grew wheat and barley, kept farm animals, and made stone tools and pots. Their large farming site dates to about 5,400 to 4,900 years ago.
People returned to the hill much later, between the 1000s and 1200s. They rebuilt the wall. They also started a small village or farm on a nearby hilltop. They buried people in an area between the two places.
