From ancient times, the great landmass of Africa has been called the dark continent. The name came from the early map makers. They knew so little of this unexplored region, they left it a blank on their charts. For centuries it remained a land of mystery, for Africa - like an ancient fortress - was surrounded by natural barriers that kept civilization out. Across the north, a vast desert: the impassible Sahara. On the west, a dense jungle; a wall of tangled underbrush along the ...