Tim Marshall delves into the strange story of Kinshasa and Brazzaville the only capitals straddling a border. Their peoples share a common culture but were split by Empires and now kept apart by a river border which has no bridge.

Presenter: Tim Marshall

(Photo: Sapeurs from a group belonging to Papa Griffe, a Sapeur leader, walks on Avenue De La Democratie, in Kinshasa, DRC. Credit: Per-Anders Pettersson/Getty Images)