Guinea–Guinea-Bissau border

The Guinea–Guinea-Bissau border is 421 km (262 m) in length and runs from the Atlantic Ocean in the south-west to the tripoint with Senegal in the north-east.

[1] The border starts in the southwest at the Atlantic coast near the mouth the Cajet/Inxanche river, just north of Guinea's Tristao Island, and then proceeds overland in a north-easterly direction.

Near the vicinity of the Guinean town of Bouto Dougaka the border proceeds overland in a northwards directions up to the Ouale river; the border then follows the Ouale and Corubal River in a C-shape, before proceeding overland northwards up to the tripoint with Senegal.

[2] Portugal began exploring the coastal areas of modern Guinea-Bissau in the mid-1400s; Bissau was founded in 1765 and became the centre of the Portuguese trade in slaves, gold and ivory in a vaguely defined area along the coast referred to as Portuguese Guinea.

The process culminated in the Berlin Conference of 1884, in which the European nations concerned agreed upon their respective territorial claims and the rules of engagements going forward.