There's a twice-weekly passenger ferry service between Gisenyi (Rubavu), Kibuye (Karongi) and Cyangugu (Rusizi). The boat makes the southbound trip from Gisenyi on Wednesdays and Saturdays, leaving from Rubona Peninsula at 7am. It arrives at Kibuye (RFr2500) around 10.30am and at Cyangugu (RFr5000) around 3.45pm. Boats head north from Cyangugu on Tuesdays and Fridays, leaving from Cyangugu around 7am.
Tickets are purchased on the boat.
The bus station is in Kamembe. There are regular services to Kigali (RFr5200, six hours) via Uwinka (RFr4000, two hours) and Huye (Butare; RFr4000, four hours). There are also several daily services for Kibuye (Karongi; RFr2200, 3½ hours).