One of the worlds great rivers flows from the heart of Africa, it cuts through the largest rainforest outside of the Amazon and contains wildlife found nowhere else on Earth. The Democratic Republic of Congo is a vast beautiful but tormented place.

The country is mineral rich but the people are among the worlds poorest, for centuries its resources have been plundered and it has been ravaged by war. The violence seems to be nonstop and now it is also plagued by Ebola but some change is coming to this country which is the size of Western Europe.

With elections finally on the horizon BBC correspondents are setting off on an expedition to follow the Congo into the heart of Africa.