The Qattara Depression in Egypt is the largest sinkhole in the world, at approximately 80 kilometers long and 120 kilometers wide. It is a desert sinkhole, and it was created naturally over millennia by the strong winds that blow across the salt beds at the base of the hole.
The Qattara Depression is located close to Cairo, Egypt. The Arabic name roughly translates to "dripping," a suitable description for the environment of sandy swamps and salt pits that fill the depression. The depression also contains the second lowest point in Africa, at 436 feet below sea level.
As of 2015, the Qattara Depression recently became the focus of debate over plans for piping water downhill into the depression from nearby seas. This would provide huge amounts of hydroelectric power while turning the depression into a lake.