Guinea shares a border with Guinea-Bissau to the northwest, Senegal to the north, Mali to the northeast, Ivory Coast to the east, Sierra Leone to the southwest and Liberia to the south. The nation forms a crescent as it curves from its southeast region to the north and west, to its northwest border with Guinea-Bissau and southwestern coast on the Atlantic Ocean. The sources of the Nige. Official languagesGovernmentUnitary LegislatureCurrency ()OverviewGuinea, officially the Republic of Guinea, is a coastal country in. It borders the to the west, to the northwest, to the north, to the northeast, to the southeast,.