This is the Northern Bald Ibis, or waldrapp (Geronticus eremita). When I first saw that featherless head, I assumed that they were carrion birds. But no, they feed on insects and small rodents. That's a good thing. Africa doesn't need another carrion eater.
There aren't many of them left anywhere, so if you meet any Turks or Egyptians or Ethiopians or Arabs, be sure to ask them to take it easy on these large birds. Let 'em be.