Nobody is sure when Ghana came into being. But some time at the beginning of the first millennium AD, it is thought that a number of clans of the Soninke people, (in modern Senegal) came together under a leader with semi-divine status, called Dinga Cisse.
The route taken by traders of the Maghreb to Ghana would have started in North Africa in Tahert, sweeping down through Sijilimasa in Southern Morocco. From there the trail went south and inland, roughly running parallel with the coast. Then it curved round to the south east through Awdaghust, finally ending up in Kumbi Saleh - the royal town of Ghana.
There were a number of reasons for Ghana's decline. The King lost his trading monopoly. At the same time drought was beginning to have a long term effect on the land and its ability to sustain cattle and cultivation. But the Empire of Ghana was also under pressure from outside forces.
There were many great African kingdoms before and during the European exploration period.
Ghana, then and now.
One of the few old Ghanaian ruins still standing.
BCC Site: The Story of Africa