The newest countries, Sudan and South Sudan, born in 2011 from the split of the former Sudan are off limits to most tourists. The difficulty in getting a visa and traveling independently, the minimal information in this regard, the lack of English spoken outside of Khartoum and the general sense of danger would put most off visiting.
But if you do you will be surprised at the locals’ hospitality, their openness despite Shariah Law, the many pyramids in Meroe and the wealth of the ancient Nubian civilisation that co-existed at the same time as the Egyptians. Like its cousin up north, Sudan also boasts great diving off the Red Sea. But beware, exploring requires permits, government paperwork and driving across the desert following a GPS so it is not for the faint hearted.