Chad · TD

Bahr el-Ghazal

The Bahr el-Ghazal is a vast, 500-kilometre dry riverbed slicing across central Chad — a geological scar from when the world's largest lake overflowed and carved its escape route toward the desert. Today this wadi is a hard clay highway of emptiness, traversed by nomadic herders and intrepid overland travellers crossing between the Sahel and the high Sahara. What makes this landscape extraordinary is its deep-time story: only about 6,000 years ago, the floor of this valley lay beneath the waters of Mega-Chad, a lake larger than the modern Caspian Sea. The Bahr el-Ghazal was that ancient lake's spillway, draining northeast toward what is now the Bodélé Depression — the dustiest place on Earth. Every grain of Saharan dust that fertilises the Amazon rainforest began its journey through this system.