New excavations at the Oued Beht site in northwestern Morocco have uncovered a massive ditch-and-rampart system dating back 3,500 to 4,000 years. Archaeologists confirm this is the oldest known defensive structure in North Africa outside of the Nile Valley. The scale of the construction forces historians to rethink prehistoric social complexity in the Maghreb, proving that local communities coordinated massive labor projects long before urban states supposedly emerged there.