I'm fascinated that this blog entry describes a city called "Kinshasa-Brazzaville." (Perhaps the author has been reading the book "BraKin"?) They are of course two distinct cities and the capitals of two distinct nation-states, which is the crux of the problem here. There may be certain respects in which they could be described as a single urban area, e.g. with respect to media markets, but that national boundary cannot be simply ignored. As for the costs of transport between Kinshasa and Brazzaville, logistical bottlenecks are only part of the problem of getting across the Congo River. Making that crossing in both directions, I found that the greatest expense was paying off the multitude of officials and shady characters merely to be allowed off the boat and out the gate in each port facility. You might gloss the problem as "cumbersome customs procedures," but it is in effect a well-organized protection racket that benefits powerful interests in each government. If you don't think such rackets are relevant, read "Africa Works" by Chabal and Daloz, or "The State in Africa" by Bayart, which show how such informal networks have sabotaged well-laid plans for economic modernization on the continent. Finally, I would have liked to see some discussion of the possibility of a bridge linking these cities. Respective governments have discussed this idea for decades but it's difficult to know whether anyone's really serious about it, or even whether a bridge would be technically feasible.