 Because of travel restrictions placed by the local chieftains, slave raiding parties, tribal wars and the difficulty of the terrain, Speke was not able to map the entire flow of the Nile from Lake Victoria north.Why he did not make more efforts to do so is not clear, but the enormous hardships of the journey must have played a large role.By January 1863 Speke and Grant reached Gondokoro in Southern Sudan, where he met Samuel Baker and his "wife".