Morocco’s 2,700km Berm in Western Sahara: History and Ecological Impact

Morocco’s Berm, a 2,700-kilometre-long wall constructed from 1980 to 1987, divides Western Sahara into Moroccan-controlled territory and the Polisario Front-controlled strip. This barrier is the world’s second-longest continuous border after the Great Wall of China and is heavily militarised.

The Berm was built to secure Morocco’s hold on the most valuable parts of Western Sahara, including its coastline, phosphate mines, and towns, after Morocco occupied the territory in 1975. The Polisario Front, supported by Algeria and representing the Sahrawi people, controls about 20% of the territory and has fought for independence since the early 1970s. The conflict remains unresolved, contributing to what the UN calls the world’s second-longest-running refugee crisis.

Alongside the Berm runs a belt of over 10 million landmines, making it the world’s longest continuous minefield. These mines have caused at least 1,427 recorded casualties by 2017, with many more likely unreported. The minefield presents ongoing risks as mines can be displaced by natural events.

Ecologically, the Berm disrupts the desert ecosystem and traditional Sahrawi pastoral life, which depends on seasonal movements along wadis — temporary rivers that sustain wells, trees, and grazing lands. The wall interrupts these natural and social systems, causing harm beyond the political and humanitarian dimensions.